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LSOF(8)                     System Manager's Manual                    LSOF(8)

NAME
       lsof - list open files

SYNOPSIS
       lsof  [  -?abChlnNOPQRtUvVX  ]  [ -A A ] [ -c c ] [ +c c ] [ +|-d d ] [
       +|-D D ] [ +|-e s ] [ +|-E ] [ +|-f [cfgGn] ] [ -F [f] ] [ -g [s]  ]  [
       -i  [i] ] [ -k k ] [ -K k ] [ +|-L [l] ] [ +|-m m ] [ +|-M ] [ -o [o] ]
       [ -p s ] [ +|-r [t[m<fmt>]] ] [ -s [p:s] ] [ -S [t] ] [ -T [t] ] [ -u s
       ] [ +|-w ] [ -x [fl] ] [ -z [z] ] [ -Z [Z] ] [ -- ] [names]

DESCRIPTION
       Lsof revision 4.95.0 lists on  its  standard  output  file  information
       about files opened by processes for the following UNIX dialects:

            Apple Darwin 9 and Mac OS X 10.[567]
            FreeBSD 8.[234], 9.0 and 1[012].0 for AMD64-based systems
            Linux 2.1.72 and above for x86-based systems
            Solaris 9, 10 and 11

       (See  the  DISTRIBUTION  section of this manual page for information on
       how to obtain the latest lsof revision.)

       An open file may be a regular file, a directory, a block special  file,
       a  character  special  file,  an executing text reference, a library, a
       stream or a network file (Internet socket,  NFS  file  or  UNIX  domain
       socket.)   A specific file or all the files in a file system may be se-
       lected by path.

       Instead of a formatted display, lsof will produce output  that  can  be
       parsed by other programs.  See the -F, option description, and the OUT-
       PUT FOR OTHER PROGRAMS section for more information.

       In  addition to producing a single output list, lsof will run in repeat
       mode.  In repeat mode it will produce output, delay,  then  repeat  the
       output  operation  until stopped with an interrupt or quit signal.  See
       the +|-r [t[m<fmt>]] option description for more information.

OPTIONS
       In the absence of any options, lsof lists all open files  belonging  to
       all active processes.

       If  any  list  request option is specified, other list requests must be
       specifically requested - e.g., if -U is specified for  the  listing  of
       UNIX  socket  files, NFS files won't be listed unless -N is also speci-
       fied; or if a user list is specified with the -u  option,  UNIX  domain
       socket  files,  belonging to users not in the list, won't be listed un-
       less the -U option is also specified.

       Normally, list options that are specifically stated are  ORed  -  i.e.,
       specifying  the  -i option without an address and the -ufoo option pro-
       duces a listing of all network files OR files  belonging  to  processes
       owned by user ``foo''.  The exceptions are:

       1) the `^' (negated) login name or user ID (UID), specified with the -u
          option;

       2) the `^' (negated) process ID (PID), specified with the -p option;

       3) the `^' (negated) process group ID (PGID), specified with the -g op-
          tion;

       4) the `^' (negated) command, specified with the -c option;

       5) the  (`^')  negated  TCP or UDP protocol state names, specified with
          the -s [p:s] option.

       Since they represent exclusions, they are applied without ORing or AND-
       ing and take effect before any other selection criteria are applied.

       The -a option may be used to AND the selections.  For example, specify-
       ing -a, -U, and -ufoo produces a listing of only UNIX socket files that
       belong to processes owned by user ``foo''.

       Caution: the -a option causes all list selection options to  be  ANDed;
       it can't be used to cause ANDing of selected pairs of selection options
       by  placing it between them, even though its placement there is accept-
       able.  Wherever -a is placed, it causes the ANDing of all selection op-
       tions.

       Items of the same selection set - command names, file descriptors, net-
       work addresses, process identifiers, user identifiers, zone names,  se-
       curity  contexts  -  are joined in a single ORed set and applied before
       the result participates  in  ANDing.   Thus,  for  example,  specifying
       -i@aaa.bbb,  -i@ccc.ddd,  -a,  and -ufff,ggg will select the listing of
       files that belong to either login ``fff'' OR ``ggg'' AND  have  network
       connections to either host aaa.bbb OR ccc.ddd.

       Options  may be grouped together following a single prefix -- e.g., the
       option set ``-a -b -C'' may be stated as -abC.  However,  since  values
       are optional following +|-f, -F, -g, -i, +|-L, -o, +|-r, -s, -S, -T, -x
       and -z.  when you have no values for them be careful that the following
       character isn't ambiguous.  For example, -Fn might represent the -F and
       -n options, or it might represent the n field identifier character fol-
       lowing  the  -F option.  When ambiguity is possible, start a new option
       with a `-' character - e.g., ``-F -n''.  If the next option is  a  file
       name,  follow the possibly ambiguous option with ``--'' - e.g., ``-F --
       name''.

       Either the `+' or the `-' prefix may be applied to a group of  options.
       Options that don't take on separate meanings for each prefix - e.g., -i
       - may be grouped under either prefix.  Thus, for example, ``+M -i'' may
       be  stated  as ``+Mi'' and the group means the same as the separate op-
       tions.  Be careful of prefix grouping when one or more options  in  the
       group  does  take on separate meanings under different prefixes - e.g.,
       +|-M; ``-iM'' is not the same request as ``-i +M''.  When in doubt, use
       separate options with appropriate prefixes.

       -? -h    These two equivalent options  select  a  usage  (help)  output
                list.   Lsof  displays a shortened form of this output when it
                detects an error in the options supplied to it, after  it  has
                displayed  messages  explaining  each  error.  (Escape the `?'
                character as your shell requires.)

       -a       causes list selection options to be ANDed, as described above.

       -A A     is available on systems configured for AFS  whose  AFS  kernel
                code  is  implemented via dynamic modules.  It allows the lsof
                user to specify A as an alternate name  list  file  where  the
                kernel  addresses  of the dynamic modules might be found.  See
                the lsof FAQ (The FAQ section gives its location.)   for  more
                information about dynamic modules, their symbols, and how they
                affect lsof.

       -b       causes  lsof  to  avoid  kernel  functions  that might block -
                lstat(2), readlink(2), and stat(2).

                See the BLOCKS AND TIMEOUTS and AVOIDING  KERNEL  BLOCKS  sec-
                tions for information on using this option.

       -c c     selects  the listing of files for processes executing the com-
                mand that begins with the characters of c.  Multiple  commands
                may  be specified, using multiple -c options.  They are joined
                in a single ORed set before participating in AND option selec-
                tion.

                If c begins with a `^', then the following characters  specify
                a command name whose processes are to be ignored (excluded.)

                If  c  begins  and ends with a slash ('/'), the characters be-
                tween the slashes are interpreted  as  a  regular  expression.
                Shell meta-characters in the regular expression must be quoted
                to  prevent  their  interpretation  by the shell.  The closing
                slash may be followed by these modifiers:

                     b    the regular expression is a basic one.
                     i    ignore the case of letters.
                     x    the regular expression is an extended one
                          (default).

                See the lsof FAQ (The FAQ section gives  its  location.)   for
                more information on basic and extended regular expressions.

                The  simple  command  specification  is tested first.  If that
                test fails, the command regular expression is applied.  If the
                simple command test succeeds, the command  regular  expression
                test  isn't  made.   This may result in ``no command found for
                regex:'' messages when lsof's -V option is specified.

       +c w     defines the maximum number of initial characters of the  name,
                supplied  by  the UNIX dialect, of the UNIX command associated
                with a process to be printed in the COMMAND column.  (The lsof
                default is nine.)

                Note that many UNIX dialects do not supply  all  command  name
                characters to lsof in the files and structures from which lsof
                obtains  command  name.   Often  dialects  limit the number of
                characters supplied in  those  sources.   For  example,  Linux
                2.4.27  and  Solaris  9  both  limit command name length to 16
                characters.

                If w is zero ('0'), all command characters supplied to lsof by
                the UNIX dialect will be printed.

                If w is less than the length of the column title, ``COMMAND'',
                it will be raised to that length.

       -C       disables the reporting of any path name  components  from  the
                kernel's  name  cache.   See the KERNEL NAME CACHE section for
                more information.

       +d s     causes lsof to search for all open instances  of  directory  s
                and  the  files  and directories it contains at its top level.
                +d does NOT descend the directory tree, rooted at s.  The +D D
                option may be used to request a  full-descent  directory  tree
                search, rooted at directory D.

                Processing  of  the  +d  option does not follow symbolic links
                within s unless the -x or -x  l option is also specified.  Nor
                does it search for open files on file system mount  points  on
                subdirectories  of  s  unless  the  -x or -x  f option is also
                specified.

                Note: the authority of the user of this option  limits  it  to
                searching  for  files  that the user has permission to examine
                with the system stat(2) function.

       -d s     specifies a list of file descriptors (FDs) to exclude from  or
                include in the output listing.  The file descriptors are spec-
                ified  in  the  comma-separated  set  s  -  e.g., ``cwd,1,3'',
                ``^6,^2''.  (There should be no spaces in the set.)

                The list is an exclusion list if all entries of the set  begin
                with  `^'.   It  is  an inclusion list if no entry begins with
                `^'.  Mixed lists are not permitted.

                A file descriptor number range may be in the set  as  long  as
                neither  member  is  empty,  both members are numbers, and the
                ending member is larger than the starting one - e.g.,  ``0-7''
                or  ``3-10''.   Ranges  may be specified for exclusion if they
                have the `^' prefix - e.g., ``^0-7''  excludes  all  file  de-
                scriptors 0 through 7.

                Multiple  file  descriptor numbers are joined in a single ORed
                set before participating in AND option selection.

                When there are exclusion and inclusion  members  in  the  set,
                lsof  reports  them as errors and exits with a non-zero return
                code.

                See the description of File Descriptor (FD) output  values  in
                the  OUTPUT  section  for  more information on file descriptor
                names.

                fd is a pseudo file descriptor name for specifying  the  whole
                range of possible file descriptor numbers.  fd does not appear
                in FD column of output.

       +D D     causes  lsof  to  search for all open instances of directory D
                and all the files and directories it contains to its  complete
                depth.

                Processing  of  the  +D  option does not follow symbolic links
                within D unless the -x or -x  l option is also specified.  Nor
                does it search for open files on file system mount  points  on
                subdirectories  of  D  unless  the  -x or -x  f option is also
                specified.

                Note: the authority of the user of this option  limits  it  to
                searching  for  files  that the user has permission to examine
                with the system stat(2) function.

                Further note: lsof may process this option slowly and  require
                a large amount of dynamic memory to do it.  This is because it
                must  descend  the entire directory tree, rooted at D, calling
                stat(2) for each file and directory, building a  list  of  all
                the  files  it finds, and searching that list for a match with
                every open file.  When directory D is large, these  steps  can
                take a long time, so use this option prudently.

       -D D     directs  lsof's use of the device cache file.  The use of this
                option is sometimes restricted.  See  the  DEVICE  CACHE  FILE
                section  and  the sections that follow it for more information
                on this option.

                -D must be followed by a function letter; the function  letter
                may  optionally  be  followed by a path name.  Lsof recognizes
                these function letters:

                     ? - report device cache file paths
                     b - build the device cache file
                     i - ignore the device cache file
                     r - read the device cache file
                     u - read and update the device cache file

                The b, r, and u functions, accompanied by  a  path  name,  are
                sometimes  restricted.   When  these functions are restricted,
                they will not appear in the description of the -D option  that
                accompanies  -h  or  -?   option output.  See the DEVICE CACHE
                FILE section and the sections that follow it for more informa-
                tion on these functions and when they're restricted.

                The ?  function reports the read-only  and  write  paths  that
                lsof can use for the device cache file, the names of any envi-
                ronment  variables whose values lsof will examine when forming
                the device cache file path, and the format  for  the  personal
                device  cache  file  path.   (Escape the `?' character as your
                shell requires.)

                When available, the b, r, and u functions may be  followed  by
                the  device  cache  file's  path.   The  standard  default  is
                .lsof_hostname in the home directory of the real user ID  that
                executes  lsof, but this could have been changed when lsof was
                configured and compiled.  (The output of the -h  and  -?   op-
                tions show the current default prefix - e.g., ``.lsof''.)  The
                suffix,  hostname,  is  the first component of the host's name
                returned by gethostname(2).

                When available, the b function directs lsof to build a new de-
                vice cache file at the default or specified path.

                The i function directs lsof to ignore the default device cache
                file and obtain its information about devices via direct calls
                to the kernel.

                The r function directs lsof to read the device  cache  at  the
                default or specified path, but prevents it from creating a new
                device  cache file when none exists or the existing one is im-
                properly structured.  The r function, when specified without a
                path name, prevents lsof from updating an  incorrect  or  out-
                dated  device  cache file, or creating a new one in its place.
                The r function is always available when it is specified  with-
                out  a path name argument; it may be restricted by the permis-
                sions of the lsof process.

                When available, the u function directs lsof to read the device
                cache file at the default or specified path, if possible,  and
                to rebuild it, if necessary.  This is the default device cache
                file function when no -D option has been specified.

       +|-e s   exempts  the  file system whose path name is s from being sub-
                jected to kernel function calls that might block.  The +e  op-
                tion  exempts  stat(2),  lstat(2)  and most readlink(2) kernel
                function calls.   The  -e  option  exempts  only  stat(2)  and
                lstat(2)  kernel function calls.  Multiple file systems may be
                specified with separate +|-e specifications and each may  have
                readlink(2) calls exempted or not.

                This option is currently implemented only for Linux.

                CAUTION:  this  option can easily be mis-applied to other than
                the file system of interest, because it uses path name  rather
                than  the more reliable device and inode numbers.  (Device and
                inode  numbers  are  acquired  via  the  potentially  blocking
                stat(2)  kernel  call  and are thus not available, but see the
                +|-m m option as a possible alternative way to  supply  device
                numbers.)   Use  this option with great care and fully specify
                the path name of the file system to be exempted.

                When open files on exempted file systems are reported, it  may
                not  be  possible to obtain all their information.  Therefore,
                some  information  columns  will  be  blank,  the   characters
                ``UNKN''  preface  the  values in the TYPE column, and the ap-
                plicable exemption option is added in parentheses to  the  end
                of  the NAME column.  (Some device number information might be
                made available via the +|-m m option.)

       +|-E     +E specifies that Linux pipe, Linux UNIX socket, Linux INET(6)
                socket closed in a local  host,  Linux  pseudoterminal  files,
                POSIX  Message  Queueue  implementation  in  Linux,  and Linux
                eventfd should be displayed with endpoint information and  the
                files of the endpoints should also be displayed.

                Note  1:  UNIX socket file endpoint information is only avail-
                able when the compile flags line of -v output contains  HASUX-
                SOCKEPT, and psudoterminal endpoint information is only avail-
                able when the compile flags line contains HASPTYEPT.

                Note  2: POSIX Message Queue file endpoint information is only
                available when mqueue file system is mounted.

                Pipe endpoint information is displayed in the NAME  column  in
                the form ``PID,cmd,FDmode'', where PID is the endpoint process
                ID;  cmd  is  the endpoint process command; FD is the endpoint
                file's descriptor; and mode  is  the  endpoint  file's  access
                mode.

                Pseudoterminal  endpoint  information is displayed in the NAME
                column as  ``->/dev/ptsmin PID,cmd,FDmode''  or  ``PID,cmd,FD-
                mode''.   The  first  form is for a master device; the second,
                for a slave device.  min is a slave device's minor device num-
                ber; and PID, cmd, FD and mode are the same as with pipe  end-
                point  information.   Note: psudoterminal endpoint information
                is only available when the compile flags  line  of  -V  output
                contains  HASPTYEPT.  In addition, this feature works on Linux
                kernels above 4.13.0.

                UNIX socket file endpoint information is displayed in the NAME
                column in the form
                ``type=TYPE ->INO=INODE PID,cmd,FDmode'', where  TYPE  is  the
                socket  type;  INODE  is  the  i-node  number of the connected
                socket; and PID, cmd, FD and mode are the same  as  with  pipe
                endpoint  information.  Note: UNIX socket file endpoint infor-
                mation is available only when the compile  flags  line  of  -v
                output contains HASUXSOCKEPT.

                INET socket file endpoint information is inserted to the value
                at the NAME column in th form
                PID,  cmd,  FD and mode are the same as with pipe endpoint in-
                formation. The endpoint information is available only  if  the
                socket  is used for local IPC; both endpoints bind to the same
                local IPv4 or IPv6 address.

                POSIX Message Queue file endpoint information is displayed  in
                the NAME column in the same form as that of pipe.

                eventfd  endpoint  information is displayed in the NAME column
                in the same form as that of pipe. This feature works on  Linux
                kernels above 5.2.0.

                Multiple  occurrences  of  this  information  can  appear in a
                file's NAME column.

                -E specifies that endpoint supported files should be displayed
                with endpoint information, but not the files of the endpoints.

       +|-f [cfgGn]
                f by itself clarifies how path name arguments are to be inter-
                preted.  When followed by c, f, g, G, or n in any  combination
                it  specifies that the listing of kernel file structure infor-
                mation is to be enabled (`+') or inhibited (`-').

                Normally a path name argument is taken to  be  a  file  system
                name  if  it  matches  a mounted-on directory name reported by
                mount(8), or if it represents a block  device,  named  in  the
                mount  output  and  associated  with a mounted directory name.
                When +f is specified, all path name arguments will be taken to
                be file system names, and lsof will complain if any  are  not.
                This  can  be  useful,  for example, when the file system name
                (mounted-on device) isn't a block device.   This  happens  for
                some CD-ROM file systems.

                When  -f  is specified by itself, all path name arguments will
                be taken to be simple files.  Thus, for example,  the  ``-f --
                /''  arguments direct lsof to search for open files with a `/'
                path name, not all open files in the `/' (root) file system.

                Be careful to make sure +f and -f are properly terminated  and
                aren't followed by a character (e.g., of the file or file sys-
                tem  name)  that  might be taken as a parameter.  For example,
                use ``--'' after +f and -f as in these examples.

                     $ lsof +f -- /file/system/name
                     $ lsof -f -- /file/name

                The listing of information from kernel  file  structures,  re-
                quested  with  the  +f [cfgGn] option form, is normally inhib-
                ited, and is not available in whole or part for some  dialects
                - e.g., /proc-based Linux kernels below 2.6.22.  When the pre-
                fix  to  f is a plus sign (`+'), these characters request file
                structure information:

                     c    file structure use count (not Linux)
                     f    file structure address (not Linux)
                     g    file flag abbreviations (Linux 2.6.22 and up)

                          Abbrev.   Flag in C code (see open(2))

                          W         O_WRONLY
                          RW        O_RDWR
                          CR        O_CREAT
                          EXCL      O_EXCL
                          NTTY      O_NOCTTY
                          TR        O_TRUNC
                          AP        O_APPEND
                          ND        O_NDELAY
                          SYN       O_SYNC
                          ASYN      O_ASYNC
                          DIR       O_DIRECT
                          DTY       O_DIRECTORY
                          NFLK      O_NOFOLLOW
                          NATM      O_NOATIME
                          DSYN      O_DSYNC
                          RSYN      O_RSYNC
                          LG        O_LARGEFILE
                          CX        O_CLOEXEC
                          TMPF      O_TMPFILE

                     G    file flags in hexadecimal (Linux 2.6.22 and up)
                     n    file structure node address (not Linux)

                When the prefix is minus (`-') the same characters disable the
                listing of the indicated values.

                File structure addresses, use  counts,  flags,  and  node  ad-
                dresses may be used to detect more readily identical files in-
                herited  by child processes and identical files in use by dif-
                ferent processes.  Lsof column output can be sorted by  output
                columns  holding  the  values and listed to identify identical
                file use, or lsof field output can be parsed by an AWK or Perl
                post-filter script, or by a C program.

       -F f     specifies a character list, f, that selects the fields  to  be
                output  for  processing  by another program, and the character
                that terminates each output field.  Each field to be output is
                specified with a single character in f.  The field  terminator
                defaults to NL, but may be changed to NUL (000).  See the OUT-
                PUT  FOR OTHER PROGRAMS section for a description of the field
                identification characters and the field output process.

                When the field selection character list is empty, all standard
                fields are selected (except the  raw  device  field,  security
                context  and  zone field for compatibility reasons) and the NL
                field terminator is used.

                When the field selection character list contains only  a  zero
                (`0'),  all  fields  are selected (except the raw device field
                for compatibility reasons) and the NUL terminator character is
                used.

                Other combinations of fields and their associated field termi-
                nator character must be set with explicit entries in f, as de-
                scribed in the OUTPUT FOR OTHER PROGRAMS section.

                When a field selection character identifies an item lsof  does
                not  normally list - e.g., PPID, selected with -R - specifica-
                tion of the field character - e.g., ``-FR'' - also selects the
                listing of the item.

                When the field selection character list  contains  the  single
                character  `?',  lsof  will  display  a help list of the field
                identification characters.  (Escape the `?' character as  your
                shell requires.)

       -g [s]   excludes  or  selects  the  listing of files for the processes
                whose optional process group IDentification (PGID) numbers are
                in the comma-separated set s - e.g., ``123'' or  ``123,^456''.
                (There should be no spaces in the set.)

                PGID  numbers  that begin with `^' (negation) represent exclu-
                sions.

                Multiple PGID numbers are joined in a single ORed  set  before
                participating  in  AND option selection.  However, PGID exclu-
                sions are applied without ORing or ANDing and take effect  be-
                fore other selection criteria are applied.

                The -g option also enables the output display of PGID numbers.
                When specified without a PGID set that's all it does.

       -i [i]   selects  the  listing  of  files any of whose Internet address
                matches the address specified in i.  If no address  is  speci-
                fied, this option selects the listing of all Internet and x.25
                (HP-UX) network files.

                If  -i4  or  -i6  is specified with no following address, only
                files of the indicated IP version,  IPv4  or  IPv6,  are  dis-
                played.   (An  IPv6  specification may be used only if the di-
                alects supports IPv6, as indicated by ``[46]'' and ``IPv[46]''
                in lsof's -h or -?   output.)   Sequentially  specifying  -i4,
                followed  by -i6 is the same as specifying -i, and vice-versa.
                Specifying -i4, or -i6 after -i is the same as specifying  -i4
                or -i6 by itself.

                Multiple  addresses  (up  to  a limit of 100) may be specified
                with multiple -i options.  (A  port  number  or  service  name
                range is counted as one address.)  They are joined in a single
                ORed set before participating in AND option selection.

                An  Internet address is specified in the form (Items in square
                brackets are optional.):

                [46][protocol][@hostname|hostaddr][:service|port]

                where:
                     46 specifies the IP version, IPv4 or IPv6
                          that applies to the following address.
                          '6' may be be specified only if the UNIX
                          dialect supports IPv6.  If neither '4' nor
                          '6' is specified, the following address
                          applies to all IP versions.
                     protocol is a protocol name - TCP, UDP
                     hostname is an Internet host name.  Unless a
                          specific IP version is specified, open
                          network files associated with host names
                          of all versions will be selected.
                     hostaddr is a numeric Internet IPv4 address in
                          dot form; or an IPv6 numeric address in
                          colon form, enclosed in brackets, if the
                          UNIX dialect supports IPv6.  When an IP
                          version is selected, only its numeric
                          addresses may be specified.
                     service is an /etc/services name - e.g., smtp -
                          or a list of them.
                     port is a port number, or a list of them.

                IPv6 options may be used only if  the  UNIX  dialect  supports
                IPv6.  To see if the dialect supports IPv6, run lsof and spec-
                ify the -h or -?  (help) option.  If the displayed description
                of  the  -i  option contains ``[46]'' and ``IPv[46]'', IPv6 is
                supported.

                IPv4 host names and addresses may not be specified if  network
                file  selection is limited to IPv6 with -i 6.  IPv6 host names
                and addresses may not be specified if network  file  selection
                is  limited  to  IPv4  with  -i  4.  When an open IPv4 network
                file's address is mapped in an IPv6 address, the  open  file's
                type  will be IPv6, not IPv4, and its display will be selected
                by '6', not '4'.

                At least one address component -  4,  6,  protocol,  hostname,
                hostaddr,  or  service - must be supplied.  The `@' character,
                leading the host specification, is always required; as is  the
                `:',  leading the port specification.  Specify either hostname
                or hostaddr.  Specify either service name list or port  number
                list.   If  a service name list is specified, the protocol may
                also need to be specified if the TCP,  UDP  and  UDPLITE  port
                numbers  for  the  service name are different.  Use any case -
                lower or upper - for protocol.

                Service names and port numbers may be combined in a list whose
                entries are separated by commas and whose  numeric  range  en-
                tries  are separated by minus signs.  There may be no embedded
                spaces, and all service names must  belong  to  the  specified
                protocol.   Since  service  names  may  contain embedded minus
                signs, the starting entry of a range can't be a service  name;
                it can be a port number, however.

                Here are some sample addresses:

                     -i6 - IPv6 only
                     TCP:25 - TCP and port 25
                     @1.2.3.4 - Internet IPv4 host address 1.2.3.4
                     @[3ffe:1ebc::1]:1234 - Internet IPv6 host address
                          3ffe:1ebc::1, port 1234
                     UDP:who - UDP who service port
                     TCP@lsof.itap:513 - TCP, port 513 and host name lsof.itap
                     tcp@foo:1-10,smtp,99 - TCP, ports 1 through 10,
                          service name smtp, port 99, host name foo
                     tcp@bar:1-smtp - TCP, ports 1 through smtp, host bar
                     :time - either TCP, UDP or UDPLITE time service port

       -K k     selects  the  listing  of tasks (threads) of processes, on di-
                alects where task (thread) reporting is supported.   (If  help
                output  -  i.e.,  the  output of the -h or -?  options - shows
                this option, then task (thread) reporting is supported by  the
                dialect.)

                If  -K  is  followed  by  a  value, k, it must be ``i''.  That
                causes lsof to ignore  tasks,  particularly  in  the  default,
                list-everything case when no other options are specified.

                When -K and -a are both specified on Linux, and the tasks of a
                main  process  are selected by other options, the main process
                will also be listed as though it were a task,  but  without  a
                task ID.  (See the description of the TID column in the OUTPUT
                section.)

                Where  the  FreeBSD version supports threads, all threads will
                be listed with their IDs.

                In general threads and tasks inherit the files of the  caller,
                but may close some and open others, so lsof always reports all
                the open files of threads and tasks.

       -k k     specifies  a  kernel  name  list file, k, in place of /vmunix,
                /mach, etc.   -k  is  not  available  under  AIX  on  the  IBM
                RISC/System 6000.

       -l       inhibits the conversion of user ID numbers to login names.  It
                is also useful when login name lookup is working improperly or
                slowly.

       +|-L [l] enables  (`+')  or  disables  (`-')  the  listing of file link
                counts, where they are available - e.g., they aren't available
                for sockets, or most FIFOs and pipes.

                When +L is specified without  a  following  number,  all  link
                counts will be listed.  When -L is specified (the default), no
                link counts will be listed.

                When  +L  is  followed  by  a number, only files having a link
                count less than that number will be listed.   (No  number  may
                follow  -L.)   A specification of the form ``+L1'' will select
                open files that have been unlinked.  A  specification  of  the
                form ``+aL1 <file_system>'' will select unlinked open files on
                the specified file system.

                For  other link count comparisons, use field output (-F) and a
                post-processing script or program.

       +|-m m   specifies an alternate kernel memory file or  activates  mount
                table supplement processing.

                The  option  form  -m  m specifies a kernel memory file, m, in
                place of /dev/kmem or /dev/mem - e.g., a crash dump file.

                The option form +m requests that a mount  supplement  file  be
                written  to  the  standard output file.  All other options are
                silently ignored.

                There will be a line in the mount  supplement  file  for  each
                mounted file system, containing the mounted file system direc-
                tory,  followed by a single space, followed by the device num-
                ber in hexadecimal "0x" format - e.g.,

                     / 0x801

                Lsof can use the mount supplement file to get  device  numbers
                for  file  systems  when  it  can't  get  them  via stat(2) or
                lstat(2).

                The option form +m m identifies m as a mount supplement file.

                Note: the +m and +m m options are not available for  all  sup-
                ported dialects.  Check the output of lsof's -h or -?  options
                to see if the +m and +m m options are available.

       +|-M     Enables (+) or disables (-) the reporting of portmapper regis-
                trations for local TCP, UDP and UDPLITE ports, where port map-
                ping is supported.  (See the last paragraph of this option de-
                scription  for information about where portmapper registration
                reporting is supported.)

                The default reporting mode is set by the lsof builder with the
                HASPMAPENABLED #define in the dialect's machine.h header file;
                lsof is distributed with the  HASPMAPENABLED  #define  deacti-
                vated, so portmapper reporting is disabled by default and must
                be requested with +M.  Specifying lsof's -h or -?  option will
                report  the  default  mode.  Disabling portmapper registration
                when it is already disabled or enabling it  when  already  en-
                abled  is  acceptable.  When portmapper registration reporting
                is enabled, lsof displays the portmapper registration (if any)
                for local TCP, UDP or UDPLITE ports in square brackets immedi-
                ately following the port numbers  or  service  names  -  e.g.,
                ``:1234[name]'' or ``:name[100083]''.  The registration infor-
                mation  may  be a name or number, depending on what the regis-
                tering program supplied to the portmapper when  it  registered
                the port.

                When  portmapper  registration  reporting is enabled, lsof may
                run a little more slowly or even become blocked when access to
                the portmapper becomes congested or stopped.  Reverse the  re-
                porting mode to determine if portmapper registration reporting
                is slowing or blocking lsof.

                For purposes of portmapper registration reporting lsof consid-
                ers  a  TCP,  UDP or UDPLITE port local if: it is found in the
                local part of its containing kernel structure; or if it is lo-
                cated in the foreign part of its containing  kernel  structure
                and  the local and foreign Internet addresses are the same; or
                if it is located in the foreign part of its containing  kernel
                structure  and the foreign Internet address is INADDR_LOOPBACK
                (127.0.0.1).  This rule may  make  lsof  ignore  some  foreign
                ports  on  machines  with multiple interfaces when the foreign
                Internet address is on a different interface  from  the  local
                one.

                See  the  lsof  FAQ (The FAQ section gives its location.)  for
                further discussion of portmapper  registration  reporting  is-
                sues.

                Portmapper  registration  reporting  is  supported only on di-
                alects that have RPC header files.  (Some Linux  distributions
                with  GlibC 2.14 do not have them.)  When portmapper registra-
                tion reporting is supported, the -h or -?   help  output  will
                show the +|-M option.

       -n       inhibits  the  conversion of network numbers to host names for
                network  files.   Inhibiting  conversion  may  make  lsof  run
                faster.   It is also useful when host name lookup is not work-
                ing properly.

       -N       selects the listing of NFS files.

       -o       directs lsof to display file offset at all times.   It  causes
                the  SIZE/OFF  output  column  title  to be changed to OFFSET.
                Note: on some UNIX dialects lsof can't obtain accurate or con-
                sistent file offset information from its kernel data  sources,
                sometimes  just  for  particular  kinds of files (e.g., socket
                files.)  Consult the lsof FAQ (The FAQ section gives its loca-
                tion.)  for more information.

                The -o and -s options are mutually exclusive; they can't  both
                be  specified.  When neither is specified, lsof displays what-
                ever value - size or offset - is appropriate and available for
                the type of the file.

       -o o     defines the number of decimal digits (o) to be  printed  after
                the  ``0t''  for  a file offset before the form is switched to
                ``0x...''.  An o value of zero (unlimited) directs lsof to use
                the ``0t'' form for all offset output.

                This option does NOT direct lsof  to  display  offset  at  all
                times;  specify -o (without a trailing number) to do that.  -o
                o only specifies the number of digits after ``0t''  in  either
                mixed  size and offset or offset-only output.  Thus, for exam-
                ple, to direct lsof to display offset at all times with a dec-
                imal digit count of 10, use:

                     -o -o 10
                or
                     -oo10

                The default number of digits allowed after ``0t'' is  normally
                8, but may have been changed by the lsof builder.  Consult the
                description  of  the -o o option in the output of the -h or -?
                option to determine the default that is in effect.

       -O       directs lsof to bypass the strategy it  uses  to  avoid  being
                blocked by some kernel operations - i.e., doing them in forked
                child  processes.   See  the  BLOCKS AND TIMEOUTS and AVOIDING
                KERNEL BLOCKS sections for more information on  kernel  opera-
                tions that may block lsof.

                While use of this option will reduce lsof startup overhead, it
                may also cause lsof to hang when the kernel doesn't respond to
                a function.  Use this option cautiously.

       -p s     excludes  or  selects  the  listing of files for the processes
                whose optional process IDentification (PID) numbers are in the
                comma-separated set s - e.g., ``123'' or ``123,^456''.  (There
                should be no spaces in the set.)

                PID numbers that begin with `^'  (negation)  represent  exclu-
                sions.

                Multiple  process  ID  numbers are joined in a single ORed set
                before participating in AND option  selection.   However,  PID
                exclusions are applied without ORing or ANDing and take effect
                before other selection criteria are applied.

       -P       inhibits the conversion of port numbers to port names for net-
                work  files.   Inhibiting  the  conversion may make lsof run a
                little faster.  It is also useful when port name lookup is not
                working properly.

       -Q       ignore failed search terms. When lsof is told  to  search  for
                users  of  a file, or for users of a device, or for a specific
                PID, or for certain protocols in use by that PID, and  so  on,
                lsof  will  return  an  error if any of the search results are
                empty. The -Q option will change this behavior  so  that  lsof
                will  instead return a successful exit code (0) even if any of
                the search results are  empty.  In  addition,  missing  search
                terms will not be reported to stderr.

       +|-r [t[c<N>][m<fmt>]]
                puts  lsof in repeat mode.  There lsof lists open files as se-
                lected by other options, delays t seconds  (default  fifteen),
                then  repeats  the  listing, delaying and listing repetitively
                until stopped by a condition defined by the prefix to the  op-
                tion.

                If  the prefix is a `-', repeat mode is endless.  Lsof must be
                terminated with an interrupt or quit signal.   `c<N>'  is  for
                specifying  the  limits  of repeating; if the number of itera-
                tions reaches at `<N>', Lsof stops itself.

                If the prefix is `+', repeat mode will end the first cycle  no
                open  files  are  listed  - and of course when lsof is stopped
                with an interrupt or quit signal.  When repeat mode  ends  be-
                cause  no files are listed, the process exit code will be zero
                if any open files were ever listed; one,  if  none  were  ever
                listed.

                Lsof  marks  the  end  of  each listing: if field output is in
                progress (the -F, option  has  been  specified),  the  default
                marker  is  `m'; otherwise the default marker is ``========''.
                The marker is followed by a NL character.

                The optional "m<fmt>" argument  specifies  a  format  for  the
                marker  line.   The  <fmt> characters following `m' are inter-
                preted as a format specification to the strftime(3)  function,
                when  both  it  and the localtime(3) function are available in
                the dialect's C library.  Consult the  strftime(3)  documenta-
                tion  for  what  may appear in its format specification.  Note
                that when field output is requested with the -F option,  <fmt>
                cannot  contain  the  NL  format, ``%n''.  Note also that when
                <fmt> contains spaces or  other  characters  that  affect  the
                shell's  interpretation of arguments, <fmt> must be quoted ap-
                propriately.

                Repeat mode reduces lsof startup overhead, so it is more effi-
                cient to use this mode than to call lsof repetitively  from  a
                shell script, for example.

                To use repeat mode most efficiently, accompany +|-r with spec-
                ification  of  other  lsof selection options, so the amount of
                kernel memory access lsof does will be kept to a minimum.  Op-
                tions that filter at the process level - e.g., -c, -g, -p,  -u
                - are the most efficient selectors.

                Repeat  mode is useful when coupled with field output (see the
                -F, option description) and a supervising awk or Perl  script,
                or a C program.

       -R       directs  lsof to list the Parent Process IDentification number
                in the PPID column.

       -s [p:s] s alone directs lsof to display file size at  all  times.   It
                causes the SIZE/OFF output column title to be changed to SIZE.
                If the file does not have a size, nothing is displayed.

                The  optional  -s  p:s form is available only for selected di-
                alects, and only when the -h or -?  help output lists it.

                When the optional form is available, the s may be followed  by
                a  protocol  name  (p), either TCP or UDP, a colon (`:') and a
                comma-separated protocol state name list,  the  option  causes
                open  TCP  and UDP files to be excluded if their state name(s)
                are in the list (s) preceded by a `^'; or  included  if  their
                name(s) are not preceded by a `^'.

                Dialects  that support this option may support only one proto-
                col.  When an unsupported protocol  is  specified,  a  message
                will  be displayed indicating state names for the protocol are
                unavailable.

                When an inclusion list is defined,  only  network  files  with
                state  names  in  the list will be present in the lsof output.
                Thus, specifying one state name means that only network  files
                with that lone state name will be listed.

                Case  is unimportant in the protocol or state names, but there
                may be no spaces and the colon (`:') separating  the  protocol
                name (p) and the state name list (s) is required.

                If  only  TCP and UDP files are to be listed, as controlled by
                the specified exclusions and inclusions, the -i option must be
                specified, too.  If only a single protocol's files are  to  be
                listed, add its name as an argument to the -i option.

                For example, to list only network files with TCP state LISTEN,
                use:

                     -iTCP -sTCP:LISTEN

                Or, for example, to list network files with all UDP states ex-
                cept Idle, use:

                     -iUDP -sUDP:^Idle

                State  names  vary with UNIX dialects, so it's not possible to
                provide a complete list.  Some common  TCP  state  names  are:
                CLOSED,  IDLE, BOUND, LISTEN, ESTABLISHED, SYN_SENT, SYN_RCDV,
                ESTABLISHED,   CLOSE_WAIT,   FIN_WAIT1,   CLOSING,   LAST_ACK,
                FIN_WAIT_2, and TIME_WAIT.  Two common UDP state names are Un-
                bound and Idle.

                See  the  lsof  FAQ (The FAQ section gives its location.)  for
                more information on how to use protocol  state  exclusion  and
                inclusion, including examples.

                The -o (without a following decimal digit count) and -s option
                (without  a  following protocol and state name list) are mutu-
                ally exclusive; they can't both be specified.  When neither is
                specified, lsof displays whatever value - size or offset -  is
                appropriate and available for the type of file.

                Since some types of files don't have true sizes - sockets, FI-
                FOs,  pipes,  etc. - lsof displays for their sizes the content
                amounts in their associated kernel buffers, if possible.

       -S [t]   specifies an optional time-out seconds value for kernel  func-
                tions - lstat(2), readlink(2), and stat(2) - that might other-
                wise  deadlock.   The  minimum for t is two; the default, fif-
                teen; when no value is specified, the default is used.

                See the BLOCKS AND TIMEOUTS section for more information.

       -T [t]   controls the reporting of some TCP/TPI information,  also  re-
                ported  by  netstat(1),  following  the network addresses.  In
                normal output the information  appears  in  parentheses,  each
                item  except  TCP  or  TPI state name identified by a keyword,
                followed by `=', separated from others by a single space:

                     <TCP or TPI state name>
                     QR=<read queue length>
                     QS=<send queue length>
                     SO=<socket options and values>
                     SS=<socket states>
                     TF=<TCP flags and values>
                     WR=<window read length>
                     WW=<window write length>

                Not all values are reported for all UNIX dialects.  Items val-
                ues (when available) are reported after the item name and '='.

                When the field output mode is in effect (See OUTPUT FOR  OTHER
                PROGRAMS.)   each  item  appears as a field with a `T' leading
                character.

                -T with no following key characters disables TCP/TPI  informa-
                tion reporting.

                -T with following characters selects the reporting of specific
                TCP/TPI information:

                     f    selects reporting of socket options,
                          states and values, and TCP flags and
                          values.
                     q    selects queue length reporting.
                     s    selects connection state reporting.
                     w    selects window size reporting.

                Not  all selections are enabled for some UNIX dialects.  State
                may be selected for all dialects and is reported  by  default.
                The -h or -?  help output for the -T option will show what se-
                lections may be used with the UNIX dialect.

                When  -T  is used to select information - i.e., it is followed
                by one or more selection characters - the displaying of  state
                is  disabled  by  default,  and it must be explicitly selected
                again in the characters following -T.  (In effect,  then,  the
                default  is equivalent to -Ts.)  For example, if queue lengths
                and state are desired, use -Tqs.

                Socket options, socket states, some socket values,  TCP  flags
                and  one TCP value may be reported (when available in the UNIX
                dialect) in the form of the names that commonly  appear  after
                SO_,  so_,  SS_, TCP_  and TF_ in the dialect's header files -
                most    often    <sys/socket.h>,     <sys/socketvar.h>     and
                <netinet/tcp_var.h>.  Consult those header files for the mean-
                ing of the flags, options, states and values.

                ``SO=''  precedes  socket  options and values; ``SS='', socket
                states; and ``TF='', TCP flags and values.

                If a flag or option has a value, the value will follow an  '='
                and   the   name   --  e.g.,  ``SO=LINGER=5'',  ``SO=QLIM=5'',
                ``TF=MSS=512''.  The following seven values may be reported:

                     Name
                     Reported  Description (Common Symbol)

                     KEEPALIVE keep alive time (SO_KEEPALIVE)
                     LINGER    linger time (SO_LINGER)
                     MSS       maximum segment size (TCP_MAXSEG)
                     PQLEN          partial listen queue connections
                     QLEN      established listen queue connections
                     QLIM      established listen queue limit
                     RCVBUF    receive buffer length (SO_RCVBUF)
                     SNDBUF    send buffer length (SO_SNDBUF)

                Details on what socket options and values, socket states,  and
                TCP  flags and values may be displayed for particular UNIX di-
                alects may be found in the answer to the  ``Why  doesn't  lsof
                report socket options, socket states, and TCP flags and values
                for  my  dialect?''  and ``Why doesn't lsof report the partial
                listen queue connection count for my dialect?''  questions  in
                the  lsof  FAQ (The FAQ section gives its location.)  On Linux
                this option also prints the state of UNIX domain sockets.

       -t       produce  terse  output  comprising  only  process  identifiers
                (without  a  header),  so  that it is easy to use programmati-
                cally. e.g.

                     # reload anything using old SSL
                     lsof -t /lib/*/libssl.so.* | xargs -r kill -HUP

                     # get list of processes and then iterate over them (Bash only)
                     mapfile -t pids < <(
                         lsof -wt /var/log/your.log
                     )
                     for pid in "${pids[@]}" ; do
                         your_command -p "$pid"
                     done

                The -t option implies the -w option.

       -u s     selects the listing of files for the user whose login names or
                user ID numbers are in  the  comma-separated  set  s  -  e.g.,
                ``abe'',  or  ``548,root''.  (There should be no spaces in the
                set.)

                Multiple login names or user ID numbers are joined in a single
                ORed set before participating in AND option selection.

                If a login name or user ID is preceded by a `^', it becomes  a
                negation - i.e., files of processes owned by the login name or
                user ID will never be listed.  A negated login name or user ID
                selection  is neither ANDed nor ORed with other selections; it
                is applied before all other selections and absolutely excludes
                the listing of the files of the process.  For example, to  di-
                rect  lsof  to  exclude the listing of files belonging to root
                processes, specify ``-u^root'' or ``-u^0''.

       -U       selects the listing of UNIX domain socket files.

       -v       selects the listing of lsof  version  information,  including:
                revision  number;  when  the  lsof binary was constructed; who
                constructed the binary and where; the  name  of  the  compiler
                used  to  construct the lsof binary; the version number of the
                compiler when readily available; the compiler and loader flags
                used to construct the lsof  binary;  and  system  information,
                typically the output of uname's -a option.

       -V       directs  lsof  to  indicate the items it was asked to list and
                failed to find - command names, file names, Internet addresses
                or files, login names, NFS files, PIDs, PGIDs, and UIDs.

                When other options  are  ANDed  to  search  options,  or  com-
                pile-time options restrict the listing of some files, lsof may
                not  report that it failed to find a search item when an ANDed
                option or compile-time option prevents the listing of the open
                file containing the located search item.

                For example, ``lsof -V -iTCP@foobar -a -d 999'' may not report
                a failure to locate open files at ``TCP@foobar'' and  may  not
                list  any,  if  none  have a file descriptor number of 999.  A
                similar situation arises when HASSECURITY  and  HASNOSOCKSECU-
                RITY  are defined at compile time and they prevent the listing
                of open files.

       +|-w     Enables (+) or disables (-) the suppression  of  warning  mes-
                sages.

                The  lsof builder may choose to have warning messages disabled
                or enabled by default.  The default warning message  state  is
                indicated  in  the  output of the -h or -?  option.  Disabling
                warning messages when they are already  disabled  or  enabling
                them when already enabled is acceptable.

                The -t option implies the -w option.

       -x [fl]  may accompany the +d and +D options to direct their processing
                to  cross  over symbolic links and|or file system mount points
                encountered when scanning the directory (+d) or directory tree
                (+D).

                If -x is specified by itself without  a  following  parameter,
                cross-over  processing  of both symbolic links and file system
                mount points is enabled.  Note that when -x is specified with-
                out a parameter, the next argument must begin with '-' or '+'.

                The optional 'f' parameter enables  file  system  mount  point
                cross-over  processing; 'l', symbolic link cross-over process-
                ing.

                The -x option may not be supplied without also supplying a  +d
                or +D option.

       -X       This is a dialect-specific option.

           AIX:
                This IBM AIX RISC/System 6000 option requests the reporting of
                executed text file and shared library references.

                WARNING: because this option uses the kernel readx() function,
                its  use  on  a  busy  AIX  system  might cause an application
                process to hang so completely that it can  neither  be  killed
                nor stopped.  I have never seen this happen or had a report of
                its  happening,  but  I think there is a remote possibility it
                could happen.

                By default use of readx() is disabled.  On AIX  5L  and  above
                lsof  may  need  setuid-root permission to perform the actions
                this option requests.

                The lsof builder may specify that the -X option be  restricted
                to  processes  whose real UID is root.  If that has been done,
                the -X option will not appear in the -h or -?  help output un-
                less the real UID of the lsof process is  root.   The  default
                lsof  distribution allows any UID to specify -X, so by default
                it will appear in the help output.

                When AIX readx() use is disabled, lsof may not be able to  re-
                port  information for all text and loader file references, but
                it may also avoid exacerbating an AIX kernel directory  search
                kernel error, known as the Stale Segment ID bug.

                The readx() function, used by lsof or any other program to ac-
                cess  some  sections of kernel virtual memory, can trigger the
                Stale Segment ID bug.  It can cause the kernel's  dir_search()
                function to believe erroneously that part of an in-memory copy
                of  a file system directory has been zeroed.  Another applica-
                tion process, distinct from lsof, asking the kernel to  search
                the   directory   -   e.g.,  by  using  open(2)  -  can  cause
                dir_search() to loop forever,  thus  hanging  the  application
                process.

                Consult  the  lsof  FAQ  (The FAQ section gives its location.)
                and the 00README file of the lsof distribution for a more com-
                plete description of the Stale Segment ID bug, its  APAR,  and
                methods for defining readx() use when compiling lsof.

           Linux:
                This Linux option requests that lsof skip the reporting of in-
                formation  on  all  open  TCP,  UDP  and UDPLITE IPv4 and IPv6
                files.

                This Linux option is most useful when the system  has  an  ex-
                tremely  large  number of open TCP, UDP and UDPLITE files, the
                processing of whose  information  in  the  /proc/net/tcp*  and
                /proc/net/udp*  files  would  take lsof a long time, and whose
                reporting is not of interest.

                Use this option with care and only when you are sure that  the
                information  you  want  lsof  to display isn't associated with
                open TCP, UDP or UDPLITE socket files.

           Solaris 10 and above:
                This Solaris 10 and above option  requests  the  reporting  of
                cached  paths for files that have been deleted - i.e., removed
                with rm(1) or unlink(2).

                The cached path is followed by the  string  `` (deleted)''  to
                indicate  that  the path by which the file was opened has been
                deleted.

                Because intervening changes made to the path -  i.e.,  renames
                with mv(1) or rename(2) - are not recorded in the cached path,
                what  lsof  reports  is  only  the  path by which the file was
                opened, not its possibly different final path.

       -z [z]   specifies how Solaris 10 and higher zone information is to  be
                handled.

                Without  a following argument - e.g., NO z - the option speci-
                fies that zone names are to be listed in the ZONE output  col-
                umn.

                The  -z option may be followed by a zone name, z.  That causes
                lsof to list only open files for processes in that zone.  Mul-
                tiple -z z option and argument pairs may be specified to  form
                a list of named zones.  Any open file of any process in any of
                the  zones  will be listed, subject to other conditions speci-
                fied by other options and arguments.

       -Z [Z]   specifies how SELinux security contexts are to be handled.  It
                and 'Z' field output  character  support  are  inhibited  when
                SELinux  is  disabled in the running Linux kernel.  See OUTPUT
                FOR OTHER PROGRAMS for more information on the 'Z' field  out-
                put character.

                Without  a following argument - e.g., NO Z - the option speci-
                fies that security contexts are to  be  listed  in  the  SECU-
                RITY-CONTEXT output column.

                The  -Z  option may be followed by a wildcard security context
                name, Z.  That  causes  lsof  to  list  only  open  files  for
                processes  in that security context.  Multiple -Z Z option and
                argument pairs may be specified to form  a  list  of  security
                contexts.  Any open file of any process in any of the security
                contexts will be listed, subject to other conditions specified
                by  other  options and arguments.  Note that Z can be A:B:C or
                *:B:C or A:B:* or *:*:C to match against the A:B:C context.

       --       The double minus sign option is a marker that signals the  end
                of  the  keyed options.  It may be used, for example, when the
                first file name begins with a minus sign.  It may also be used
                when the absence of a value for the last keyed option must  be
                signified by the presence of a minus sign in the following op-
                tion and before the start of the file names.

       names    These  are  path  names  of  specific files to list.  Symbolic
                links are resolved before use.  The first name  may  be  sepa-
                rated from the preceding options with the ``--'' option.

                If  a name is the mounted-on directory of a file system or the
                device of the file system, lsof will list all the  files  open
                on  the file system.  To be considered a file system, the name
                must match a mounted-on directory name in mount(8) output,  or
                match  the name of a block device associated with a mounted-on
                directory name.  The +|-f option may be used to force lsof  to
                consider a name a file system identifier (+f) or a simple file
                (-f).

                If  name  is  a path to a directory that is not the mounted-on
                directory name of a file system, it is treated just as a regu-
                lar file is treated -  i.e.,  its  listing  is  restricted  to
                processes that have it open as a file or as a process-specific
                directory,  such as the root or current working directory.  To
                request that lsof look for open files inside a directory name,
                use the +d s and +D D options.

                If a name is the base name of a family of multiplexed files  -
                e.g,  AIX's  /dev/pt[cs]  -  lsof will list all the associated
                multiplexed  files  on  the  device  that  are  open  -  e.g.,
                /dev/pt[cs]/1, /dev/pt[cs]/2, etc.

                If  a  name  is  a  UNIX domain socket name, lsof will usually
                search for it by the characters of the name alone - exactly as
                it is specified and is recorded in the  kernel  socket  struc-
                ture.   (See  the next paragraph for an exception to that rule
                for Linux.)  Specifying a relative path - e.g.,  ./file  -  in
                place  of  the  file's absolute path - e.g., /tmp/file - won't
                work because lsof must match the characters you  specify  with
                what it finds in the kernel UNIX domain socket structures.

                If a name is a Linux UNIX domain socket name, in one case lsof
                is  able  to search for it by its device and inode number, al-
                lowing name to be a relative path.  The case requires that the
                absolute path -- i.e., one beginning with  a  slash  ('/')  be
                used  by  the  process  that  created the socket, and hence be
                stored in the /proc/net/unix file; and it requires  that  lsof
                be  able to obtain the device and node numbers of both the ab-
                solute path in /proc/net/unix and name via successful  stat(2)
                system  calls.   When  those  conditions are met, lsof will be
                able to search for the UNIX domain socket when some path to it
                is is specified in name.  Thus, for example, if  the  path  is
                /dev/log, and an lsof search is initiated when the working di-
                rectory is /dev, then name could be ./log.

                If  a name is none of the above, lsof will list any open files
                whose device and inode match that of the specified path name.

                If you have also specified the -b option, the only  names  you
                may safely specify are file systems for which your mount table
                supplies  alternate  device  numbers.  See the AVOIDING KERNEL
                BLOCKS and ALTERNATE DEVICE NUMBERS sections for more informa-
                tion.

                Multiple file names are joined in a  single  ORed  set  before
                participating in AND option selection.

AFS
       Lsof  supports the recognition of AFS files for these dialects (and AFS
       versions):

            AIX 4.1.4 (AFS 3.4a)
            HP-UX 9.0.5 (AFS 3.4a)
            Linux 1.2.13 (AFS 3.3)
            Solaris 2.[56] (AFS 3.4a)

       It may recognize AFS files on other versions of these dialects, but has
       not been tested there.  Depending on how AFS is implemented,  lsof  may
       recognize  AFS files in other dialects, or may have difficulties recog-
       nizing AFS files in the supported dialects.

       Lsof may have trouble identifying all aspects of AFS files in supported
       dialects when AFS kernel support is  implemented  via  dynamic  modules
       whose  addresses  do not appear in the kernel's variable name list.  In
       that case, lsof may have to guess at the identity  of  AFS  files,  and
       might  not be able to obtain volume information from the kernel that is
       needed for calculating AFS volume node numbers.  When lsof  can't  com-
       pute volume node numbers, it reports blank in the NODE column.

       The  -A  A  option is available in some dialect implementations of lsof
       for specifying the name list file where dynamic module kernel addresses
       may be found.  When this option is available, it will be listed in  the
       lsof help output, presented in response to the -h or -?

       See the lsof FAQ (The FAQ section gives its location.)  for more infor-
       mation  about  dynamic modules, their symbols, and how they affect lsof
       options.

       Because AFS path lookups don't seem to participate in the kernel's name
       cache operations, lsof can't identify  path  name  components  for  AFS
       files.

SECURITY
       Lsof  has  three features that may cause security concerns.  First, its
       default compilation mode allows anyone to list all open files with  it.
       Second,  by default it creates a user-readable and user-writable device
       cache file in the home directory of the  real  user  ID  that  executes
       lsof.   (The  list-all-open-files and device cache features may be dis-
       abled when lsof is compiled.)  Third, its -k and -m options name alter-
       nate kernel name list or memory files.

       Restricting the listing of all open files is  controlled  by  the  com-
       pile-time  HASSECURITY and HASNOSOCKSECURITY options.  When HASSECURITY
       is defined, lsof will allow only the root user to list all open  files.
       The  non-root  user may list only open files of processes with the same
       user IDentification number as the real  user  ID  number  of  the  lsof
       process (the one that its user logged on with).

       However,  if HASSECURITY and HASNOSOCKSECURITY are both defined, anyone
       may list open socket files, provided they are selected with the -i  op-
       tion.

       When HASSECURITY is not defined, anyone may list all open files.

       Help  output,  presented in response to the -h or -?  option, gives the
       status of the HASSECURITY and HASNOSOCKSECURITY definitions.

       See the Security section of the 00README file of the lsof  distribution
       for  information on building lsof with the HASSECURITY and HASNOSOCKSE-
       CURITY options enabled.

       Creation and use of a user-readable and user-writable device cache file
       is controlled by the compile-time HASDCACHE  option.   See  the  DEVICE
       CACHE  FILE  section and the sections that follow it for details on how
       its path is formed.  For security considerations  it  is  important  to
       note  that  in the default lsof distribution, if the real user ID under
       which lsof is executed is root, the device cache file will  be  written
       in root's home directory - e.g., / or /root.  When HASDCACHE is not de-
       fined, lsof does not write or attempt to read a device cache file.

       When  HASDCACHE is defined, the lsof help output, presented in response
       to the -h, -D?, or -?  options, will provide device cache file handling
       information.  When HASDCACHE is not defined, the -h or -?  output  will
       have no -D option description.

       Before  you  decide to disable the device cache file feature - enabling
       it improves the performance of lsof by reducing the startup overhead of
       examining all the nodes in /dev (or /devices) - read the discussion  of
       it  in the 00DCACHE file of the lsof distribution and the lsof FAQ (The
       FAQ section gives its location.)

       WHEN IN DOUBT, YOU CAN TEMPORARILY DISABLE THE USE OF THE DEVICE  CACHE
       FILE WITH THE -Di OPTION.

       When lsof user declares alternate kernel name list or memory files with
       the  -k  and  -m options, lsof checks the user's authority to read them
       with access(2).  This is intended to  prevent  whatever  special  power
       lsof's modes might confer on it from letting it read files not normally
       accessible via the authority of the real user ID.

OUTPUT
       This  section  describes the information lsof lists for each open file.
       See the OUTPUT FOR OTHER PROGRAMS section for additional information on
       output that can be processed by another program.

       Lsof only outputs printable (declared so by isprint(3)) 8  bit  charac-
       ters.   Non-printable characters are printed in one of three forms: the
       C ``\[bfrnt]'' form; the control character `^' form (e.g., ``^@'');  or
       hexadecimal  leading ``\x'' form (e.g., ``\xab'').  Space is non-print-
       able in the COMMAND column (``\x20'') and printable elsewhere.

       For some dialects - if HASSETLOCALE is defined  in  the  dialect's  ma-
       chine.h  header file - lsof will print the extended 8 bit characters of
       a language locale.  The lsof process must be supplied a language locale
       environment variable (e.g., LANG) whose value represents a  known  lan-
       guage  locale in which the extended characters are considered printable
       by isprint(3).  Otherwise lsof considers the extended  characters  non-
       printable  and  prints  them  according  to its rules for non-printable
       characters, stated above.  Consult your dialect's setlocale(3) man page
       for the names of other environment variables that may be used in  place
       of LANG - e.g., LC_ALL, LC_CTYPE, etc.

       Lsof's  language  locale support for a dialect also covers wide charac-
       ters - e.g., UTF-8 - when HASSETLOCALE and HASWIDECHAR are  defined  in
       the  dialect's  machine.h header file, and when a suitable language lo-
       cale has been defined in the appropriate environment variable  for  the
       lsof  process.  Wide characters are printable under those conditions if
       iswprint(3) reports them to be.  If  HASSETLOCALE,  HASWIDECHAR  and  a
       suitable language locale aren't defined, or if iswprint(3) reports wide
       characters  that  aren't  printable, lsof considers the wide characters
       non-printable and prints each of their 8 bits according  to  its  rules
       for non-printable characters, stated above.

       Consult  the  answers to the "Language locale support" questions in the
       lsof FAQ (The FAQ section gives its location.) for more information.

       Lsof dynamically sizes the output columns each time it runs, guarantee-
       ing that each column is a minimum size.  It also guarantees  that  each
       column is separated from its predecessor by at least one space.

       COMMAND    contains  the  first nine characters of the name of the UNIX
                  command associated with the process.  If a non-zero w  value
                  is  specified  to  the  +c w option, the column contains the
                  first w characters of the name of the UNIX  command  associ-
                  ated with the process up to the limit of characters supplied
                  to lsof by the UNIX dialect.  (See the description of the +c
                  w  command  or  the  lsof FAQ for more information.  The FAQ
                  section gives its location.)

                  If w is less than the length of  the  column  title,  ``COM-
                  MAND'', it will be raised to that length.

                  If  a zero w value is specified to the +c w option, the col-
                  umn contains all the characters of the name of the UNIX com-
                  mand associated with the process.

                  All command name characters maintained by the kernel in  its
                  structures  are  displayed  in field output when the command
                  name descriptor (`c') is  specified.   See  the  OUTPUT  FOR
                  OTHER  COMMANDS  section  for information on selecting field
                  output and the associated command name descriptor.

       PID        is the Process IDentification number of the process.

       TID        is the task (thread) IDentification number, if task (thread)
                  reporting is supported by the dialect and a task (thread) is
                  being listed.  (If help output - i.e., the output of the  -h
                  or  -?   options - shows this option, then task (thread) re-
                  porting is supported by the dialect.)

                  A blank TID column in Linux indicates a process  -  i.e.,  a
                  non-task.

       TASKCMD    is  the  task command name.  Generally this will be the same
                  as the process named in the COMMAND column,  but  some  task
                  implementations  (e.g.,  Linux)  permit a task to change its
                  command name.

                  The TASKCMD column width is subject to the same size limita-
                  tion as the COMMAND column.

       ZONE       is the Solaris 10 and higher zone name.  This column must be
                  selected with the -z option.

       SECURITY-CONTEXT
                  is the SELinux security context.  This column  must  be  se-
                  lected  with  the -Z option.  Note that the -Z option is in-
                  hibited when SELinux is disabled in the running  Linux  ker-
                  nel.

       PPID       is  the Parent Process IDentification number of the process.
                  It is only displayed when the -R option has been specified.

       PGID       is the process group IDentification number  associated  with
                  the  process.   It  is only displayed when the -g option has
                  been specified.

       USER       is the user ID number or login name of the user to whom  the
                  process  belongs,  usually  the  same  as reported by ps(1).
                  However, on Linux USER is the user ID number or  login  that
                  owns  the  directory  in  /proc where lsof finds information
                  about the process.  Usually that is the same value  reported
                  by  ps(1),  but  may differ when the process has changed its
                  effective user ID.  (See the -l option description  for  in-
                  formation  on  when  a  user ID number or login name is dis-
                  played.)

       FD         is the File Descriptor number of the file or:

                       cwd  current working directory;
                       Lnn  library references (AIX);
                       err  FD information error (see NAME column);
                       jld  jail directory (FreeBSD);
                       ltx  shared library text (code and data);
                       Mxx  hex memory-mapped type number xx.
                       m86  DOS Merge mapped file;
                       mem  memory-mapped file;
                       mmap memory-mapped device;
                       pd   parent directory;
                       rtd  root directory;
                       tr   kernel trace file (OpenBSD);
                       txt  program text (code and data);
                       v86  VP/ix mapped file;

                  FD is followed by one of these  characters,  describing  the
                  mode under which the file is open:

                       r for read access;
                       w for write access;
                       u for read and write access;
                       space if mode unknown and no lock
                            character follows;
                       `-' if mode unknown and lock
                            character follows.

                  The  mode character is followed by one of these lock charac-
                  ters, describing the type of lock applied to the file:

                       N for a Solaris NFS lock of unknown type;
                       r for read lock on part of the file;
                       R for a read lock on the entire file;
                       w for a write lock on part of the file;
                       W for a write lock on the entire file;
                       u for a read and write lock of any length;
                       U for a lock of unknown type;
                       x for an SCO OpenServer Xenix lock on part      of  the
                  file;
                       X for an SCO OpenServer Xenix lock on the entire file;
                       space if there is no lock.

                  See  the  LOCKS section for more information on the lock in-
                  formation character.

                  The FD column contents constitutes a single field for  pars-
                  ing in post-processing scripts.

       TYPE       is  the  type  of  the node associated with the file - e.g.,
                  GDIR, GREG, VDIR, VREG, etc.

                  or ``IPv4'' for an IPv4 socket;

                  or ``IPv6'' for an open IPv6 network file - even if its  ad-
                  dress is IPv4, mapped in an IPv6 address;

                  or ``ax25'' for a Linux AX.25 socket;

                  or ``inet'' for an Internet domain socket;

                  or ``lla'' for a HP-UX link level access file;

                  or ``rte'' for an AF_ROUTE socket;

                  or ``sock'' for a socket of unknown domain;

                  or ``unix'' for a UNIX domain socket;

                  or ``x.25'' for an HP-UX x.25 socket;

                  or ``BLK'' for a block special file;

                  or ``CHR'' for a character special file;

                  or ``DEL'' for a Linux map file that has been deleted;

                  or ``DIR'' for a directory;

                  or ``DOOR'' for a VDOOR file;

                  or ``FIFO'' for a FIFO special file;

                  or ``KQUEUE'' for a BSD style kernel event queue file;

                  or ``LINK'' for a symbolic link file;

                  or ``MPB'' for a multiplexed block file;

                  or ``MPC'' for a multiplexed character file;

                  or  ``NOFD'' for a Linux /proc/<PID>/fd directory that can't
                  be opened -- the directory path appears in the NAME  column,
                  followed by an error message;

                  or ``PAS'' for a /proc/as file;

                  or ``PAXV'' for a /proc/auxv file;

                  or ``PCRE'' for a /proc/cred file;

                  or ``PCTL'' for a /proc control file;

                  or ``PCUR'' for the current /proc process;

                  or ``PCWD'' for a /proc current working directory;

                  or ``PDIR'' for a /proc directory;

                  or ``PETY'' for a /proc executable type (etype);

                  or ``PFD'' for a /proc file descriptor;

                  or ``PFDR'' for a /proc file descriptor directory;

                  or ``PFIL'' for an executable /proc file;

                  or ``PFPR'' for a /proc FP register set;

                  or ``PGD'' for a /proc/pagedata file;

                  or ``PGID'' for a /proc group notifier file;

                  or ``PIPE'' for pipes;

                  or ``PLC'' for a /proc/lwpctl file;

                  or ``PLDR'' for a /proc/lpw directory;

                  or ``PLDT'' for a /proc/ldt file;

                  or ``PLPI'' for a /proc/lpsinfo file;

                  or ``PLST'' for a /proc/lstatus file;

                  or ``PLU'' for a /proc/lusage file;

                  or ``PLWG'' for a /proc/gwindows file;

                  or ``PLWI'' for a /proc/lwpsinfo file;

                  or ``PLWS'' for a /proc/lwpstatus file;

                  or ``PLWU'' for a /proc/lwpusage file;

                  or ``PLWX'' for a /proc/xregs file;

                  or ``PMAP'' for a /proc map file (map);

                  or ``PMEM'' for a /proc memory image file;

                  or ``PNTF'' for a /proc process notifier file;

                  or ``POBJ'' for a /proc/object file;

                  or ``PODR'' for a /proc/object directory;

                  or  ``POLP''  for  an  old format /proc light weight process
                  file;

                  or ``POPF'' for an old format /proc PID file;

                  or ``POPG'' for an old format /proc page data file;

                  or ``PORT'' for a SYSV named pipe;

                  or ``PREG'' for a /proc register file;

                  or ``PRMP'' for a /proc/rmap file;

                  or ``PRTD'' for a /proc root directory;

                  or ``PSGA'' for a /proc/sigact file;

                  or ``PSIN'' for a /proc/psinfo file;

                  or ``PSTA'' for a /proc status file;

                  or ``PSXMQ'' for a POSIX message queue file;

                  or ``PSXSEM'' for a POSIX semaphore file;

                  or ``PSXSHM'' for a POSIX shared memory file;

                  or ``PTS'' for a /dev/pts file;

                  or ``PUSG'' for a /proc/usage file;

                  or ``PW'' for a /proc/watch file;

                  or ``PXMP'' for a /proc/xmap file;

                  or ``REG'' for a regular file;

                  or ``SMT'' for a shared memory transport file;

                  or ``STSO'' for a stream socket;

                  or ``UNNM'' for an unnamed type file;

                  or ``XNAM'' for an OpenServer Xenix special file of  unknown
                  type;

                  or ``XSEM'' for an OpenServer Xenix semaphore file;

                  or ``XSD'' for an OpenServer Xenix shared data file;

                  or  the  four  type  number octets if the corresponding name
                  isn't known.

       FILE-ADDR  contains the kernel file structure address when f  has  been
                  specified to +f;

       FCT        contains  the  file  reference  count  from  the kernel file
                  structure when c has been specified to +f;

       FILE-FLAG  when g or G has been specified to +f,  this  field  contains
                  the  contents  of  the  f_flag[s]  member of the kernel file
                  structure and the kernel's per-process open file  flags  (if
                  available);  `G' causes them to be displayed in hexadecimal;
                  `g', as short-hand names; two lists may  be  displayed  with
                  entries  separated by commas, the lists separated by a semi-
                  colon (`;'); the first list may contain short-hand names for
                  f_flag[s] values from the following table:

                       AIO       asynchronous I/O (e.g., FAIO)
                       AP        append
                       ASYN      asynchronous I/O (e.g., FASYNC)
                       BAS       block, test, and set in use
                       BKIU      block if in use
                       BL        use block offsets
                       BSK       block seek
                       CA        copy avoid
                       CIO       concurrent I/O
                       CLON      clone
                       CLRD      CL read
                       CR        create
                       DF        defer
                       DFI       defer IND
                       DFLU      data flush
                       DIR       direct
                       DLY       delay
                       DOCL      do clone
                       DSYN      data-only integrity
                       DTY       must be a directory
                       EVO       event only
                       EX        open for exec
                       EXCL      exclusive open
                       FSYN      synchronous writes
                       GCDF      defer during unp_gc() (AIX)
                       GCMK      mark during unp_gc() (AIX)
                       GTTY      accessed via /dev/tty
                       HUP       HUP in progress
                       KERN      kernel
                       KIOC      kernel-issued ioctl
                       LCK       has lock
                       LG        large file
                       MBLK      stream message block
                       MK        mark
                       MNT       mount
                       MSYN      multiplex synchronization
                       NATM      don't update atime
                       NB        non-blocking I/O
                       NBDR      no BDRM check
                       NBIO      SYSV non-blocking I/O
                       NBF       n-buffering in effect
                       NC        no cache
                       ND        no delay
                       NDSY      no data synchronization
                       NET       network
                       NFLK      don't follow links
                       NMFS      NM file system
                       NOTO      disable background stop
                       NSH       no share
                       NTTY      no controlling TTY
                       OLRM      OLR mirror
                       PAIO      POSIX asynchronous I/O
                       PATH      path
                       PP        POSIX pipe
                       R         read
                       RC        file and record locking cache
                       REV       revoked
                       RSH       shared read
                       RSYN      read synchronization
                       RW        read and write access
                       SL        shared lock
                       SNAP      cooked snapshot
                       SOCK      socket
                       SQSH      Sequent shared set on open
                       SQSV      Sequent SVM set on open
                       SQR       Sequent set repair on open
                       SQS1      Sequent full shared open
                       SQS2      Sequent partial shared open
                       STPI      stop I/O
                       SWR       synchronous read
                       SYN       file integrity while writing
                       TCPM      avoid TCP collision
                       TMPF      temporary file
                       TR        truncate
                       W         write
                       WKUP      parallel I/O synchronization
                       WTG       parallel I/O synchronization
                       VH        vhangup pending
                       VTXT      virtual text
                       XL        exclusive lock

                  this list of names was derived from F* #define's in  dialect
                  header   files   <fcntl.h>,   <linux</fs.h>,  <sys/fcntl.c>,
                  <sys/fcntlcom.h>, and <sys/file.h>; see  the  lsof.h  header
                  file for a list showing the correspondence between the above
                  short-hand names and the header file definitions;

                  the second list (after the semicolon) may contain short-hand
                  names  for  kernel per-process open file flags from this ta-
                  ble:

                       ALLC      allocated
                       BR        the file has been read
                       BHUP      activity stopped by SIGHUP
                       BW        the file has been written
                       CLSG      closing
                       CX        close-on-exec (see fcntl(F_SETFD))
                       LCK       lock was applied
                       MP        memory-mapped
                       OPIP      open pending - in progress
                       RSVW      reserved wait
                       SHMT      UF_FSHMAT set (AIX)
                       USE       in use (multi-threaded)

       NODE-ID    (or INODE-ADDR for some dialects) contains a unique  identi-
                  fier  for  the  file node (usually the kernel vnode or inode
                  address, but also occasionally a concatenation of device and
                  node number) when n has been specified to +f;

       DEVICE     contains the device numbers,  separated  by  commas,  for  a
                  character  special, block special, regular, directory or NFS
                  file;

                  or ``memory'' for a memory  file  system  node  under  Tru64
                  UNIX;

                  or  the address of the private data area of a Solaris socket
                  stream;

                  or a kernel reference address that identifies the file  (The
                  kernel  reference  address may be used for FIFO's, for exam-
                  ple.);

                  or the base address or device name of a Linux  AX.25  socket
                  device.

                  Usually  only the lower thirty two bits of Tru64 UNIX kernel
                  addresses are displayed.

       SIZE, SIZE/OFF, or OFFSET
                  is the size of the file or the  file  offset  in  bytes.   A
                  value  is  displayed in this column only if it is available.
                  Lsof displays whatever value - size or offset - is appropri-
                  ate for the type of the file and the version of lsof.

                  On some UNIX dialects lsof can't obtain accurate or  consis-
                  tent  file  offset information from its kernel data sources,
                  sometimes just for particular kinds of files  (e.g.,  socket
                  files.)  In other cases, files don't have true sizes - e.g.,
                  sockets, FIFOs, pipes - so lsof displays for their sizes the
                  content  amounts it finds in their kernel buffer descriptors
                  (e.g., socket buffer size counts or  TCP/IP  window  sizes.)
                  Consult  the  lsof FAQ (The FAQ section gives its location.)
                  for more information.

                  The file size is displayed in decimal; the  offset  is  nor-
                  mally  displayed in decimal with a leading ``0t'' if it con-
                  tains 8 digits or less; in hexadecimal with a leading ``0x''
                  if it is longer than 8 digits.  (Consult the -o o option de-
                  scription for information on when 8 might  default  to  some
                  other value.)

                  Thus  the  leading ``0t'' and ``0x'' identify an offset when
                  the column may contain both a size and an offset (i.e.,  its
                  title is SIZE/OFF).

                  If the -o option is specified, lsof always displays the file
                  offset (or nothing if no offset is available) and labels the
                  column  OFFSET.   The  offset  always  begins with ``0t'' or
                  ``0x'' as described above.

                  The lsof user can control the switch from ``0t''  to  ``0x''
                  with  the -o o option.  Consult its description for more in-
                  formation.

                  If the -s option is specified, lsof always displays the file
                  size (or nothing if no size is  available)  and  labels  the
                  column  SIZE.  The -o and -s options are mutually exclusive;
                  they can't both be specified.

                  For files that don't have a fixed size - e.g., don't  reside
                  on a disk device - lsof will display appropriate information
                  about  the  current  size  or  position of the file if it is
                  available in the kernel structures that define the file.

       NLINK      contains the file link count when +L has been specified;

       NODE       is the node number of a local file;

                  or the inode number of an NFS file in the server host;

                  or the Internet protocol type - e.g, ``TCP'';

                  or ``STR'' for a stream;

                  or ``CCITT'' for an HP-UX x.25 socket;

                  or the IRQ or inode number of a Linux AX.25 socket device.

       NAME       is the name of the mount point and file system on which  the
                  file resides;

                  or  the  name of a file specified in the names option (after
                  any symbolic links have been resolved);

                  or the name of a character special or block special device;

                  or the local and remote  Internet  addresses  of  a  network
                  file;  the  local  host  name  or IP number is followed by a
                  colon (':'), the port, ``->'', and the two-part  remote  ad-
                  dress; IP addresses may be reported as numbers or names, de-
                  pending  on  the  +|-M,  -n, and -P options; colon-separated
                  IPv6 numbers are  enclosed  in  square  brackets;  IPv4  IN-
                  ADDR_ANY  and  IPv6  IN6_IS_ADDR_UNSPECIFIED  addresses, and
                  zero port numbers are represented by an  asterisk  ('*');  a
                  UDP  destination  address  may  be followed by the amount of
                  time elapsed since the last packet was sent to the  destina-
                  tion;  TCP, UDP and UDPLITE remote addresses may be followed
                  by TCP/TPI information in parentheses - state (e.g.,  ``(ES-
                  TABLISHED)'',  ``(Unbound)''), queue sizes, and window sizes
                  (not all dialects) - in a fashion similar to what netstat(1)
                  reports; see the -T option description or the description of
                  the TCP/TPI field in OUTPUT FOR OTHER PROGRAMS for more  in-
                  formation on state, queue size, and window size;

                  or the address or name of a UNIX domain socket, possibly in-
                  cluding  a  stream clone device name, a file system object's
                  path name, local and foreign kernel addresses,  socket  pair
                  information, and a bound vnode address;

                  or the local and remote mount point names of an NFS file;

                  or ``STR'', followed by the stream name;

                  or  a  stream  character device name, followed by ``->'' and
                  the stream name or a list of stream module names,  separated
                  by ``->'';

                  or ``STR:'' followed by the SCO OpenServer stream device and
                  module names, separated by ``->'';

                  or  system  directory name, `` -- '', and as many components
                  of the path name as lsof can find in the kernel's name cache
                  for selected dialects (See the KERNEL NAME CACHE section for
                  more information.);

                  or ``PIPE->'', followed by a Solaris kernel pipe destination
                  address;

                  or ``COMMON:'', followed by  the  vnode  device  information
                  structure's device name, for a Solaris common vnode;

                  or  the  address family, followed by a slash (`/'), followed
                  by fourteen comma-separated  bytes  of  a  non-Internet  raw
                  socket address;

                  or  the  HP-UX  x.25  local address, followed by the virtual
                  connection number (if any), followed by the  remote  address
                  (if any);

                  or ``(dead)'' for disassociated Tru64 UNIX files - typically
                  terminal  files  that  have  been flagged with the TIOCNOTTY
                  ioctl and closed by daemons;

                  or ``rd=<offset>'' and ``wr=<offset>'' for the values of the
                  read and write offsets of a FIFO;

                  or ``clone n:/dev/event'' for SCO OpenServer file clones  of
                  the /dev/event device, where n is the minor device number of
                  the file;

                  or  ``(socketpair:  n)'' for a Solaris 2.6, 8, 9  or 10 UNIX
                  domain socket, created by the socketpair(3N)  network  func-
                  tion;

                  or  ``no  PCB'' for socket files that do not have a protocol
                  block associated  with  them,  optionally  followed  by  ``,
                  CANTSENDMORE''  if  sending on the socket has been disabled,
                  or ``, CANTRCVMORE'' if receiving on  the  socket  has  been
                  disabled (e.g., by the shutdown(2) function);

                  or the local and remote addresses of a Linux IPX socket file
                  in  the  form <net>:[<node>:]<port>, followed in parentheses
                  by the transmit and receive queue sizes, and the  connection
                  state;

                  or  ``dgram''  or ``stream'' for the type UnixWare 7.1.1 and
                  above in-kernel UNIX domain sockets,  followed  by  a  colon
                  (':')  and  the  local path name when available, followed by
                  ``->'' and the remote path name or kernel socket address  in
                  hexadecimal when available;

                  or the association value, association index, endpoint value,
                  local  address,  local  port, remote address and remote port
                  for Linux SCTP sockets;

                  or ``protocol: '' followed by the  Linux  socket's  protocol
                  attribute.

       For  dialects  that support a ``namefs'' file system, allowing one file
       to be attached to another with fattach(3C), lsof  will  add  ``(FA:<ad-
       dress1><direction><address2>)''  to  the  NAME  column.  <address1> and
       <address2> are hexadecimal vnode addresses.  <direction> will be ``<-''
       if <address2> has been fattach'ed to this vnode whose address  is  <ad-
       dress1>; and ``->'' if <address1>, the vnode address of this vnode, has
       been fattach'ed to <address2>.  <address1> may be omitted if it already
       appears in the DEVICE column.

       Lsof  may  add  two parenthetical notes to the NAME column for open So-
       laris 10 files: ``(?)'' if lsof considers the path name of questionable
       accuracy; and ``(deleted)'' if the -X option  has  been  specified  and
       lsof  detects  the open file's path name has been deleted.  Consult the
       lsof FAQ (The FAQ section gives its location.)  for more information on
       these NAME column additions.

LOCKS
       Lsof can't adequately report the wide  variety  of  UNIX  dialect  file
       locks  in a single character.  What it reports in a single character is
       a compromise between the information it finds in  the  kernel  and  the
       limitations of the reporting format.

       Moreover, when a process holds several byte level locks on a file, lsof
       only  reports  the  status of the first lock it encounters.  If it is a
       byte level lock, then the lock character will be reported in lower case
       - i.e., `r', `w', or `x' - rather than the upper  case  equivalent  re-
       ported for a full file lock.

       Generally  lsof can only report on locks held by local processes on lo-
       cal files.  When a local process sets a  lock  on  a  remotely  mounted
       (e.g.,  NFS)  file,  the  remote  server  host usually records the lock
       state.  One exception is Solaris - at some patch levels of 2.3, and  in
       all  versions  above 2.4, the Solaris kernel records information on re-
       mote locks in local structures.

       Lsof has trouble reporting locks for some UNIX dialects.   Consult  the
       BUGS section of this manual page or the lsof FAQ (The FAQ section gives
       its location.)  for more information.

OUTPUT FOR OTHER PROGRAMS
       When  the -F option is specified, lsof produces output that is suitable
       for processing by another program - e.g, an awk or Perl script, or a  C
       program.

       Each unit of information is output in a field that is identified with a
       leading character and terminated by a NL (012) (or a NUL (000) if the 0
       (zero) field identifier character is specified.)  The data of the field
       follows  immediately  after  the field identification character and ex-
       tends to the field terminator.

       It is possible to think of field output as process and  file  sets.   A
       process  set  begins  with a field whose identifier is `p' (for process
       IDentifier (PID)).  It extends to the beginning of the next  PID  field
       or  the beginning of the first file set of the process, whichever comes
       first.  Included in the process set are fields that identify  the  com-
       mand, the process group IDentification (PGID) number, the task (thread)
       ID (TID), and the user ID (UID) number or login name.

       A  file  set  begins with a field whose identifier is `f' (for file de-
       scriptor).  It is followed by lines that  describe  the  file's  access
       mode, lock state, type, device, size, offset, inode, protocol, name and
       stream  module  names.  It extends to the beginning of the next file or
       process set, whichever comes first.

       When the NUL (000) field terminator has been selected with the 0 (zero)
       field identifier character, lsof ends each process and file set with  a
       NL (012) character.

       Lsof  always  produces one field, the PID (`p') field.  In repeat mode,
       the marker (`m') is also produced.  All other fields  may  be  declared
       optionally  in  the field identifier character list that follows the -F
       option.  When a field selection character identifies an item lsof  does
       not normally list - e.g., PPID, selected with -R - specification of the
       field character - e.g., ``-FR'' - also selects the listing of the item.

       Lsof  version  from  4.88 to 4.93.2 always produced one more field, the
       file descriptor (`f') field. However, lsof in this version doesn't pro-
       duce it. This change is for supporting the use case that a  user  needs
       only the PID field, and doesn't need the file descriptor field. Specify
       `f' explicitly if you need the field.

       It is entirely possible to select a set of fields that cannot easily be
       parsed - e.g., if the field descriptor field is not selected, it may be
       difficult  to  identify  file sets.  To help you avoid this difficulty,
       lsof supports the -F option; it selects the output of all  fields  with
       NL  terminators  (the  -F0 option pair selects the output of all fields
       with NUL terminators).  For compatibility reasons neither  -F  nor  -F0
       select the raw device field.

       These  are  the  fields  that  lsof will produce.  The single character
       listed first is the field identifier.

            a    file access mode
            c    process command name (all characters from proc or
                 user structure)
            C    file structure share count
            d    file's device character code
            D    file's major/minor device number (0x<hexadecimal>)
            f    file descriptor
            F    file structure address (0x<hexadecimal>)
            G    file flaGs (0x<hexadecimal>; names if +fg follows)
            g    process group ID
            i    file's inode number
            K    tasK ID
            k    link count
            l    file's lock status
            L    process login name
            m    marker between repeated output (always selected in repeat mode)
            M    the task comMand name
            n    file name, comment, Internet address
            N    node identifier (ox<hexadecimal>
            o    file's offset (0t<decimal> or 0x<hexadecimal>, see -o o)
            p    process ID (always selected)
            P    protocol name
            r    raw device number (0x<hexadecimal>)
            R    parent process ID
            s    file's size (decimal)
            S    file's stream identification
            t    file's type
            T    TCP/TPI information, identified by prefixes (the
                 `=' is part of the prefix):
                     QR=<read queue size>
                     QS=<send queue size>
                     SO=<socket options and values> (not all dialects)
                     SS=<socket states> (not all dialects)
                     ST=<connection state>
                     TF=<TCP flags and values> (not all dialects)
                     WR=<window read size>  (not all dialects)
                     WW=<window write size>  (not all dialects)
                 (TCP/TPI information isn't reported for all supported
                   UNIX dialects. The -h or -? help output for the
                   -T option will show what TCP/TPI reporting can be
                   requested.)
            u    process user ID
            z    Solaris 10 and higher zone name
            Z    SELinux security context (inhibited when SELinux is disabled)
            0    use NUL field terminator character in place of NL
            1-9  dialect-specific field identifiers (The output
                 of -F? identifies the information to be found
                 in dialect-specific fields.)

       You can get on-line help information on these characters and their  de-
       scriptions by specifying the -F?  option pair.  (Escape the `?' charac-
       ter  as  your shell requires.)  Additional information on field content
       can be found in the OUTPUT section.

       As an example, ``-F pcfn'' will select the process  ID  (`p'),  command
       name (`c'), file descriptor (`f') and file name (`n') fields with an NL
       field terminator character; ``-F pcfn0'' selects the same output with a
       NUL (000) field terminator character.

       Lsof  doesn't  produce  all  fields for every process or file set, only
       those that are available.  Some fields are mutually exclusive: file de-
       vice characters and file major/minor device numbers; file inode  number
       and  protocol  name; file name and stream identification; file size and
       offset.  One or the other member of these mutually exclusive sets  will
       appear in field output, but not both.

       Normally  lsof ends each field with a NL (012) character.  The 0 (zero)
       field identifier character may be specified to change the field  termi-
       nator  character  to  a  NUL  (000).  A NUL terminator may be easier to
       process with xargs (1), for example, or  with  programs  whose  quoting
       mechanisms  may  not  easily  cope  with the range of characters in the
       field output.  When the NUL field terminator is in use, lsof ends  each
       process and file set with a NL (012).

       Three aids to producing programs that can process lsof field output are
       included  in  the  lsof  distribution.   The  first is a C header file,
       lsof_fields.h, that contains symbols for the field identification char-
       acters, indexes for storing them in a table,  and  explanation  strings
       that may be compiled into programs.  Lsof uses this header file.

       The  second  aid  is a set of sample scripts that process field output,
       written in awk, Perl 4, and Perl 5.  They're  located  in  the  scripts
       subdirectory of the lsof distribution.

       The  third aid is the C library used for the lsof test suite.  The test
       suite is written in C and uses field output to validate the correct op-
       eration of lsof.  The library can be found in the tests/LTlib.c file of
       the  lsof  distribution.   The  library  uses  the   first   aid,   the
       lsof_fields.h header file.

BLOCKS AND TIMEOUTS
       Lsof  can  be blocked by some kernel functions that it uses - lstat(2),
       readlink(2), and stat(2).  These functions are stalled in  the  kernel,
       for  example,  when the hosts where mounted NFS file systems reside be-
       come inaccessible.

       Lsof attempts to break these blocks with timers  and  child  processes,
       but  the  techniques are not wholly reliable.  When lsof does manage to
       break a block, it will report the break with  an  error  message.   The
       messages may be suppressed with the -t and -w options.

       The  default  timeout value may be displayed with the -h or -?  option,
       and it may be changed with the -S [t] option.  The minimum for t is two
       seconds, but you should avoid small values, since slow  system  respon-
       siveness  can  cause  short timeouts to expire unexpectedly and perhaps
       stop lsof before it can produce any output.

       When lsof has to break a block during its access of mounted file system
       information, it normally  continues,  although  with  less  information
       available to display about open files.

       Lsof  can  also be directed to avoid the protection of timers and child
       processes when using the kernel functions that might block by  specify-
       ing  the  -O  option.  While this will allow lsof to start up with less
       overhead, it exposes lsof completely  to  the  kernel  situations  that
       might block it.  Use this option cautiously.

AVOIDING KERNEL BLOCKS
       You  can use the -b option to tell lsof to avoid using kernel functions
       that would block.  Some cautions apply.

       First, using this option usually requires that your system  supply  al-
       ternate  device  numbers in place of the device numbers that lsof would
       normally obtain with the lstat(2) and stat(2)  kernel  functions.   See
       the  ALTERNATE DEVICE NUMBERS section for more information on alternate
       device numbers.

       Second, you can't specify names for lsof to locate unless they're  file
       system  names.  This is because lsof needs to know the device and inode
       numbers of files listed with names in the lsof options, and the -b  op-
       tion  prevents lsof from obtaining them.  Moreover, since lsof only has
       device numbers for the file systems that have alternates,  its  ability
       to  locate files on file systems depends completely on the availability
       and accuracy of the alternates.  If no alternates are available, or  if
       they're incorrect, lsof won't be able to locate files on the named file
       systems.

       Third,  if  the names of your file system directories that lsof obtains
       from your system's mount table are symbolic links, lsof won't  be  able
       to  resolve  the  links.   This is because the -b option causes lsof to
       avoid the kernel readlink(2)  function  it  uses  to  resolve  symbolic
       links.

       Finally, using the -b option causes lsof to issue warning messages when
       it  needs  to use the kernel functions that the -b option directs it to
       avoid.  You can suppress these messages by specifying  the  -w  option,
       but  if  you do, you won't see the alternate device numbers reported in
       the warning messages.

ALTERNATE DEVICE NUMBERS
       On some dialects, when lsof has to break a block because it  can't  get
       information  about  a  mounted file system via the lstat(2) and stat(2)
       kernel functions, or because you specified the -b option, lsof can  ob-
       tain  some of the information it needs - the device number and possibly
       the file system type - from the system mount table.  When that is  pos-
       sible,  lsof  will report the device number it obtained.  (You can sup-
       press the report by specifying the -w option.)

       You can assist this process if your mount table is  supported  with  an
       /etc/mtab  or /etc/mnttab file that contains an options field by adding
       a ``dev=xxxx'' field for mount points that do not have one in their op-
       tions strings.  Note: you must be able to edit the file  -  i.e.,  some
       mount  tables like recent Solaris /etc/mnttab or Linux /proc/mounts are
       read-only and can't be modified.

       You may also be able to supply device numbers using the +m and +m m op-
       tions, provided they are supported by your dialect.  Check  the  output
       of  lsof's  -h  or  -?   options  to see if the +m and +m m options are
       available.

       The ``xxxx'' portion of the field is the hexadecimal value of the  file
       system's device number.  (Consult the st_dev field of the output of the
       lstat(2) and stat(2) functions for the appropriate values for your file
       systems.)   Here's  an example from a Sun Solaris 2.6 /etc/mnttab for a
       file system remotely mounted via NFS:

            nfs  ignore,noquota,dev=2a40001

       There's an advantage to having ``dev=xxxx'' entries in your mount table
       file, especially for file systems that  are  mounted  from  remote  NFS
       servers.   When  a  remote  server crashes and you want to identify its
       users by running lsof on one of its clients,  lsof  probably  won't  be
       able to get output from the lstat(2) and stat(2) functions for the file
       system.   If  it  can  obtain  the file system's device number from the
       mount table, it will be able to display the files open on  the  crashed
       NFS server.

       Some  dialects  that  do not use an ASCII /etc/mtab or /etc/mnttab file
       for the mount table may still provide an alternative device  number  in
       their internal mount tables.  This includes AIX, Apple Darwin, FreeBSD,
       NetBSD, OpenBSD, and Tru64 UNIX.  Lsof knows how to obtain the alterna-
       tive  device  number for these dialects and uses it when its attempt to
       lstat(2) or stat(2) the file system is blocked.

       If you're not sure your dialect supplies alternate device  numbers  for
       file  systems from its mount table, use this lsof incantation to see if
       it reports any alternate device numbers:

              lsof -b

       Look for standard error file warning  messages  that  begin  ``assuming
       "dev=xxxx" from ...''.

KERNEL NAME CACHE
       Lsof is able to examine the kernel's name cache or use other kernel fa-
       cilities  (e.g., the ADVFS 4.x tag_to_path() function under Tru64 UNIX)
       on some dialects for most file system types, excluding AFS, and extract
       recently used path name components from  it.   (AFS  file  system  path
       lookups  don't use the kernel's name cache; some Solaris VxFS file sys-
       tem operations apparently don't use it, either.)

       Lsof reports the complete paths it finds in the NAME column.   If  lsof
       can't  report  all  components in a path, it reports in the NAME column
       the file system name, followed by a space, two `-' characters,  another
       space,  and  the  name  components it has located, separated by the `/'
       character.

       When lsof is run in repeat mode - i.e., with the -r option specified  -
       the  extent  to  which  it can report path name components for the same
       file may vary from  cycle  to  cycle.   That's  because  other  running
       processes  can  cause  the kernel to remove entries from its name cache
       and replace them with others.

       Lsof's use of the kernel name cache to identify the paths of files  can
       lead  it to report incorrect components under some circumstances.  This
       can happen when the kernel name cache uses device and node number as  a
       key  (e.g., SCO OpenServer) and a key on a rapidly changing file system
       is reused.  If the UNIX dialect's kernel doesn't purge the  name  cache
       entry  for a file when it is unlinked, lsof may find a reference to the
       wrong entry in the cache.  The lsof FAQ (The FAQ section gives its  lo-
       cation.)  has more information on this situation.

       Lsof can report path name components for these dialects:

            FreeBSD
            HP-UX
            Linux
            NetBSD
            NEXTSTEP
            OpenBSD
            OPENSTEP
            SCO OpenServer
            SCO|Caldera UnixWare
            Solaris
            Tru64 UNIX

       Lsof can't report path name components for these dialects:

            AIX

       If you want to know why lsof can't report path name components for some
       dialects, see the lsof FAQ (The FAQ section gives its location.)

DEVICE CACHE FILE
       Examining  all members of the /dev (or /devices) node tree with stat(2)
       functions can be time consuming.  What's  more,  the  information  that
       lsof needs - device number, inode number, and path - rarely changes.

       Consequently, lsof normally maintains an ASCII text file of cached /dev
       (or  /devices) information (exception: the /proc-based Linux lsof where
       it's not needed.)  The local system administrator who builds  lsof  can
       control  the  way  the device cache file path is formed, selecting from
       these options:

            Path from the -D option;
            Path from an environment variable;
            System-wide path;
            Personal path (the default);
            Personal path, modified by an environment variable.

       Consult the output of the -h, -D? , or -?  help options for the current
       state of device cache support.   The  help  output  lists  the  default
       read-mode  device cache file path that is in effect for the current in-
       vocation of lsof.  The -D?  option output lists the read-only and write
       device cache file paths, the names of any applicable environment  vari-
       ables, and the personal device cache path format.

       Lsof  can  detect  that the current device cache file has been acciden-
       tally or maliciously modified by integrity checks, including the compu-
       tation and verification of a sixteen bit Cyclic Redundancy Check  (CRC)
       sum  on the file's contents.  When lsof senses something wrong with the
       file, it issues a warning and attempts to remove the current cache file
       and create a new copy, but only to a path that the process can  legiti-
       mately write.

       The  path  from which a lsof process may attempt to read a device cache
       file may not be the same as the  path  to  which  it  can  legitimately
       write.   Thus when lsof senses that it needs to update the device cache
       file, it may choose a different path for writing it from the path  from
       which it read an incorrect or outdated version.

       If  available,  the -Dr option will inhibit the writing of a new device
       cache file.  (It's always available when specified without a path  name
       argument.)

       When  a  new  device  is added to the system, the device cache file may
       need to be recreated.  Since lsof compares  the  mtime  of  the  device
       cache  file  with  the mtime and ctime of the /dev (or /devices) direc-
       tory, it usually detects that a new device has been added; in that case
       lsof issues a warning message and attempts to rebuild the device  cache
       file.

       Whenever  lsof writes a device cache file, it sets its ownership to the
       real UID of the executing process, and its permission  modes  to  0600,
       this restricting its reading and writing to the file's owner.

LSOF PERMISSIONS THAT AFFECT DEVICE CACHE FILE ACCESS
       Two permissions of the lsof executable affect its ability to access de-
       vice cache files.  The permissions are set by the local system adminis-
       trator when lsof is installed.

       The  first  and  rarer permission is setuid-root.  It comes into effect
       when lsof is executed; its effective UID is then root, while  its  real
       (i.e.,  that  of the logged-on user) UID is not.  The lsof distribution
       recommends that versions for these dialects run setuid-root.

            HP-UX 11.11 and 11.23
            Linux

       The second and more common permission is setgid.  It comes into  effect
       when  the  effective  group  IDentification  number  (GID)  of the lsof
       process is set to one that can access kernel  memory  devices  -  e.g.,
       ``kmem'', ``sys'', or ``system''.

       An  lsof process that has setgid permission usually surrenders the per-
       mission after it has accessed the kernel memory devices.  When it  does
       that,  lsof  can  allow more liberal device cache path formations.  The
       lsof distribution recommends that versions for these dialects run  set-
       gid and be allowed to surrender setgid permission.

            AIX 5.[12] and 5.3-ML1
            Apple Darwin 7.x Power Macintosh systems
            FreeBSD 4.x, 4.1x, 5.x and [6789].x for x86-based systems
            FreeBSD 5.x, [6789].x and 1[012].8for Alpha, AMD64 and Sparc64
                based systems
            HP-UX 11.00
            NetBSD 1.[456], 2.x and 3.x for Alpha, x86, and SPARC-based
                systems
            NEXTSTEP 3.[13] for NEXTSTEP architectures
            OpenBSD 2.[89] and 3.[0-9] for x86-based systems
            OPENSTEP 4.x
            SCO OpenServer Release 5.0.6 for x86-based systems
            SCO|Caldera UnixWare 7.1.4 for x86-based systems
            Solaris 2.6, 8, 9 and 10
            Tru64 UNIX 5.1

       (Note: lsof for AIX 5L and above needs setuid-root permission if its -X
       option is used.)

       Lsof for these dialects does not support a device cache, so the permis-
       sions given to the executable don't apply to the device cache file.

            Linux

DEVICE CACHE FILE PATH FROM THE -D OPTION
       The  -D  option  provides limited means for specifying the device cache
       file path.  Its ?  function will report the read-only and write  device
       cache file paths that lsof will use.

       When  the  -D  b, r, and u functions are available, you can use them to
       request that the cache file be built in a specific location  (b[path]);
       read  but not rebuilt (r[path]); or read and rebuilt (u[path]).  The b,
       r, and u functions are restricted under some conditions.  They are  re-
       stricted when the lsof process is setuid-root.  The path specified with
       the r function is always read-only, even when it is available.

       The  b,  r,  and  u functions are also restricted when the lsof process
       runs setgid and lsof doesn't surrender the setgid permission.  (See the
       LSOF PERMISSIONS THAT AFFECT DEVICE CACHE FILE  ACCESS  section  for  a
       list of implementations that normally don't surrender their setgid per-
       mission.)

       A further -D function, i (for ignore), is always available.

       When  available,  the  b function tells lsof to read device information
       from the kernel with the stat(2) function and build a device cache file
       at the indicated path.

       When available, the r function tells lsof  to  read  the  device  cache
       file,  but  not  update  it.   When a path argument accompanies -Dr, it
       names the device cache file path.  The r function is  always  available
       when it is specified without a path name argument.  If lsof is not run-
       ning  setuid-root and surrenders its setgid permission, a path name ar-
       gument may accompany the r function.

       When available, the u function tells lsof to attempt to  read  and  use
       the  device  cache file.  If it can't read the file, or if it finds the
       contents of the file incorrect or outdated, it  will  read  information
       from  the kernel, and attempt to write an updated version of the device
       cache file, but only to a path it considers  legitimate  for  the  lsof
       process effective and real UIDs.

DEVICE CACHE PATH FROM AN ENVIRONMENT VARIABLE
       Lsof's  second  choice for the device cache file is the contents of the
       LSOFDEVCACHE environment variable.  It avoids this choice if  the  lsof
       process is setuid-root, or the real UID of the process is root.

       A  further  restriction  applies to a device cache file path taken from
       the LSOFDEVCACHE environment variable: lsof will  not  write  a  device
       cache file to the path if the lsof process doesn't surrender its setgid
       permission.   (See  the  LSOF PERMISSIONS THAT AFFECT DEVICE CACHE FILE
       ACCESS section for information on implementations that don't  surrender
       their setgid permission.)

       The  local system administrator can disable the use of the LSOFDEVCACHE
       environment variable or change its name when  building  lsof.   Consult
       the output of -D?  for the environment variable's name.

SYSTEM-WIDE DEVICE CACHE PATH
       The  local system administrator may choose to have a system-wide device
       cache file when building lsof.  That file will generally be constructed
       by a special system administration procedure when the system is  booted
       or  when  the contents of /dev or /devices) changes.  If defined, it is
       lsof's third device cache file path choice.

       You can tell that a system-wide device cache file is in effect for your
       local installation by examining the lsof help option output - i.e., the
       output from the -h or -?  option.

       Lsof will never write to the system-wide device cache file path by  de-
       fault.   It must be explicitly named with a -D function in a root-owned
       procedure.  Once the file has been written, the procedure  must  change
       its  permission  modes to 0644 (owner-read and owner-write, group-read,
       and other-read).

PERSONAL DEVICE CACHE PATH (DEFAULT)
       The default device cache file path of  the  lsof  distribution  is  one
       recorded  in  the  home  directory  of the real UID that executes lsof.
       Added to the home directory is a second  path  component  of  the  form
       .lsof_hostname.

       This is lsof's fourth device cache file path choice, and is usually the
       default.  If a system-wide device cache file path was defined when lsof
       was  built, this fourth choice will be applied when lsof can't find the
       system-wide device cache file.  This is the only  time  lsof  uses  two
       paths when reading the device cache file.

       The  hostname part of the second component is the base name of the exe-
       cuting host, as returned by gethostname(2).  The base name  is  defined
       to  be  the  characters  preceding the first `.'  in the gethostname(2)
       output, or all the gethostname(2) output if it contains no `.'.

       The device cache file belongs to  the  user  ID  and  is  readable  and
       writable  by  the  user ID alone - i.e., its modes are 0600.  Each dis-
       tinct real user ID on a given host that executes lsof  has  a  distinct
       device  cache file.  The hostname part of the path distinguishes device
       cache files in an NFS-mounted home directory into  which  device  cache
       files are written from several different hosts.

       The  personal device cache file path formed by this method represents a
       device cache file that lsof will attempt to read, and will  attempt  to
       write  should  it not exist or should its contents be incorrect or out-
       dated.

       The -Dr option without a path name argument will inhibit the writing of
       a new device cache file.

       The -D?  option will list the format specification for constructing the
       personal device cache file.  The conversions used in the format  speci-
       fication are described in the 00DCACHE file of the lsof distribution.

MODIFIED PERSONAL DEVICE CACHE PATH
       If  this  option is defined by the local system administrator when lsof
       is built, the LSOFPERSDCPATH environment variable contents may be  used
       to add a component of the personal device cache file path.

       The  LSOFPERSDCPATH  variable  contents are inserted in the path at the
       place marked by the local system administrator with the ``%p''  conver-
       sion  in  the HASPERSDC format specification of the dialect's machine.h
       header file.  (It's placed right after the home directory  in  the  de-
       fault lsof distribution.)

       Thus, for example, if LSOFPERSDCPATH contains ``LSOF'', the home direc-
       tory  is ``/Homes/abe'', the host name is ``lsof.itap.purdue.edu'', and
       the HASPERSDC format is the default (``%h/%p.lsof_%L''),  the  modified
       personal device cache file path is:

            /Homes/abe/LSOF/.lsof_vic

       The  LSOFPERSDCPATH  environment  variable  is  ignored  when  the lsof
       process is setuid-root or when the real UID of the process is root.

       Lsof will not write to a modified personal device cache  file  path  if
       the  lsof  process  doesn't surrender setgid permission.  (See the LSOF
       PERMISSIONS THAT AFFECT DEVICE CACHE FILE ACCESS section for a list  of
       implementations that normally don't surrender their setgid permission.)

       If,  for example, you want to create a sub-directory of personal device
       cache file paths by using the LSOFPERSDCPATH  environment  variable  to
       name  it,  and  lsof  doesn't surrender its setgid permission, you will
       have to allow lsof to create device cache files at  the  standard  per-
       sonal path and move them to your subdirectory with shell commands.

       The  local  system  administrator may: disable this option when lsof is
       built; change the name of the environment variable from  LSOFPERSDCPATH
       to  something else; change the HASPERSDC format to include the personal
       path component in another place; or exclude the personal path component
       entirely.  Consult the output of the -D?  option  for  the  environment
       variable's name and the HASPERSDC format specification.

DIAGNOSTICS
       Errors are identified with messages on the standard error file.

       Lsof returns a one (1) if any error was detected, including the failure
       to locate command names, file names, Internet addresses or files, login
       names, NFS files, PIDs, PGIDs, or UIDs it was asked to list.  If the -V
       option  is  specified, lsof will indicate the search items it failed to
       list.  If the -Q option is specified, lsof will ignore any search  item
       failures  and  only return an error if something unusual and unrecover-
       able happened.

       It returns a zero (0) if no errors were detected and if either  the  -Q
       option  was specified or it was able to list some information about all
       the specified search arguments.

       When lsof cannot open access to /dev (or /devices) or one of its subdi-
       rectories, or get information on a file in them with stat(2), it issues
       a warning message and continues.  That lsof will issue warning messages
       about inaccessible files in /dev (or /devices) is indicated in its help
       output - requested with the -h or >B -?  options -  with the message:

            Inaccessible /dev warnings are enabled.

       The warning message may be suppressed with the -w option.  It may  also
       have been suppressed by the system administrator when lsof was compiled
       by the setting of the WARNDEVACCESS definition.  In this case, the out-
       put from the help options will include the message:

            Inaccessible /dev warnings are disabled.

       Inaccessible  device  warning messages usually disappear after lsof has
       created a working device cache file.

EXAMPLES
       For a more extensive set of examples, documented more  fully,  see  the
       00QUICKSTART file of the lsof distribution.

       To list all open files, use:

              lsof

       To list all open Internet, x.25 (HP-UX), and UNIX domain files, use:

              lsof -i -U

       To  list all open IPv4 network files in use by the process whose PID is
       1234, use:

              lsof -i 4 -a -p 1234

       If it's okay for PID 1234 to not exist, or for PID 1234 to not have any
       open IPv4 network files, add -Q :

              lsof -Q -i 4 -a -p 1234

       Presuming the UNIX dialect supports IPv6, to list only open  IPv6  net-
       work files, use:

              lsof -i 6

       To  list all files using any protocol on ports 513, 514, or 515 of host
       wonderland.cc.purdue.edu, use:

              lsof -i @wonderland.cc.purdue.edu:513-515

       To list all files using any protocol on any port of  mace.cc.purdue.edu
       (cc.purdue.edu is the default domain), use:

              lsof -i @mace

       To  list  all  open  files  for login name ``abe'', or user ID 1234, or
       process 456, or process 123, or process 789, use:

              lsof -p 456,123,789 -u 1234,abe

       To list all open files on device /dev/hd4, use:

              lsof /dev/hd4

       To find the process that has /u/abe/foo open without worrying if  there
       are none, use:

              lsof -Q /u/abe/foo

       To take action only if a process has /u/abe/foo open, use:

              lsof /u/abe/foo  echo "still in use"

       To send a SIGHUP to the processes that have /u/abe/bar open, use:

              kill -HUP `lsof -t /u/abe/bar`

       To  find any open file, including an open UNIX domain socket file, with
       the name /dev/log, use:

              lsof /dev/log

       To find processes  with  open  files  on  the  NFS  file  system  named
       /nfs/mount/point whose server is inaccessible, and presuming your mount
       table supplies the device number for /nfs/mount/point, use:

              lsof -b /nfs/mount/point

       To do the preceding search with warning messages suppressed, use:

              lsof -bw /nfs/mount/point

       To ignore the device cache file, use:

              lsof -Di

       To  obtain PID and command name field output for each process, file de-
       scriptor, file device number, and file inode number for  each  file  of
       each process, use:

              lsof -FpcfDi

       To  list  the files at descriptors 1 and 3 of every process running the
       lsof command for login ID ``abe'' every 10 seconds, use:

              lsof -c lsof -a -d 1 -d 3 -u abe -r10

       To list the current working directory of processes  running  a  command
       that is exactly four characters long and has an 'o' or 'O' in character
       three, use this regular expression form of the -c c option:

              lsof -c /^..o.$/i -a -d cwd

       To  find an IP version 4 socket file by its associated numeric dot-form
       address, use:

              lsof -i@128.210.15.17

       To find an IP version 6 socket file (when  the  UNIX  dialect  supports
       IPv6) by its associated numeric colon-form address, use:

              lsof -i@[0:1:2:3:4:5:6:7]

       To  find  an  IP  version 6 socket file (when the UNIX dialect supports
       IPv6) by an associated numeric colon-form address that has a run of ze-
       roes in it - e.g., the loop-back address - use:

              lsof -i@[::1]

       To obtain a repeat mode marker line that  contains  the  current  time,
       use:

              lsof -rm====%T====

       To add spaces to the previous marker line, use:

              lsof -r "m==== %T ===="

BUGS
       Since  lsof  reads  kernel  memory  in its search for open files, rapid
       changes in kernel memory may produce unpredictable results.

       When a file has multiple record locks, the lock status character  (fol-
       lowing  the  file  descriptor) is derived from a test of the first lock
       structure, not from any combination of the individual record locks that
       might be described by multiple lock structures.

       Lsof can't search for files with restrictive access permissions by name
       unless it is installed with root set-UID permission.  Otherwise  it  is
       limited  to  searching for files to which its user or its set-GID group
       (if any) has access permission.

       The display of the destination address of a raw socket (e.g., for ping)
       depends on the UNIX operating system.  Some dialects store the destina-
       tion address in the raw socket's protocol control block, some do not.

       Lsof can't always represent Solaris device numbers in the same way that
       ls(1) does.  For example, the major and minor device numbers  that  the
       lstat(2) and stat(2) functions report for the directory on which CD-ROM
       files  are mounted (typically /cdrom) are not the same as the ones that
       it reports for the device on which CD-ROM files are mounted  (typically
       /dev/sr0).  (Lsof reports the directory numbers.)

       The  support for /proc file systems is available only for BSD and Tru64
       UNIX dialects, Linux,  and  dialects  derived  from  SYSV  R4  -  e.g.,
       FreeBSD, NetBSD, OpenBSD, Solaris, UnixWare.

       Some  /proc  file  items - device number, inode number, and file size -
       are unavailable in some dialects.  Searching for files in a /proc  file
       system may require that the full path name be specified.

       No  text (txt) file descriptors are displayed for Linux processes.  All
       entries for files other than the current working  directory,  the  root
       directory, and numerical file descriptors are labeled mem descriptors.

       Lsof  can't  search  for  Tru64 UNIX named pipes by name, because their
       kernel implementation of lstat(2) returns an improper device number for
       a named pipe.

       Lsof can't report fully or correctly on HP-UX 9.01,  10.20,  and  11.00
       locks  because  of  insufficient access to kernel data or errors in the
       kernel data.  See the lsof FAQ (The FAQ section  gives  its  location.)
       for details.

       The  AIX  SMT file type is a fabrication.  It's made up for file struc-
       tures whose type (15) isn't defined in the AIX  /usr/include/sys/file.h
       header  file.   One  way  to  create  such  file structures is to run X
       clients with the DISPLAY variable set to ``:0.0''.

       The +|-f[cfn] option is not supported under /proc-based Linux lsof, be-
       cause it doesn't read kernel structures from kernel memory.

ENVIRONMENT
       Lsof may access these environment variables.

       LANG              defines a language locale.  See setlocale(3) for  the
                         names of other variables that can be used in place of
                         LANG - e.g., LC_ALL, LC_TYPE, etc.

       LSOFDEVCACHE      defines the path to a device cache file.  See the DE-
                         VICE  CACHE PATH FROM AN ENVIRONMENT VARIABLE section
                         for more information.

       LSOFPERSDCPATH    defines the middle component of a  modified  personal
                         device  cache  file  path.  See the MODIFIED PERSONAL
                         DEVICE CACHE PATH section for more information.

FAQ
       Frequently-asked questions and their answers (an FAQ) are available  in
       the 00FAQ file of the lsof distribution.

       That latest version of the file is found at:

              https://github.com/lsof-org/lsof/blob/master/00FAQ

FILES
       /dev/kmem         kernel virtual memory device

       /dev/mem          physical memory device

       /dev/swap         system paging device

       .lsof_hostname    lsof's  device  cache  file (The suffix, hostname, is
                         the first component of the host's  name  returned  by
                         gethostname(2).)

AUTHORS
       Lsof  was  written by Victor A.Abell <abe@purdue.edu> of Purdue Univer-
       sity.  Since version 4.93.0, the  lsof-org  team  at  GitHub  maintains
       lsof.   Many  others  have  contributed to lsof.  They're listed in the
       00CREDITS file of the lsof distribution.

DISTRIBUTION
       The latest distribution of lsof is available at

              https://github.com/lsof-org/lsof/releases

SEE ALSO
       Not all the following manual pages may exist in every UNIX  dialect  to
       which lsof has been ported.

       access(2),  awk(1),  crash(1),  fattach(3C), ff(1), fstat(8), fuser(1),
       gethostname(2),  isprint(3),  kill(1),  localtime(3),  lstat(2),   mod-
       load(8),  mount(8),  netstat(1),  ofiles(8L),  open(2), perl(1), ps(1),
       readlink(2), setlocale(3), stat(2), strftime(3), time(2), uname(1).

                                Revision-4.95.0                        LSOF(8)

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