PROCPS_MISC(3) Library Functions Manual PROCPS_MISC(3)
NAME
procps_misc - API for miscellaneous information in the /proc filesystem
SYNOPSIS
#include <libproc2/misc.h>
Platform Particulars
long procps_cpu_count (void);
long procps_hertz_get (void);
unsigned int procps_pid_length (void);
int procps_linux_version (void);
Runtime Particulars
int procps_loadavg (double *av1, double *av5, double *av15);
int procps_uptime (double *uptime_secs, double *idle_secs);
char *procps_uptime_sprint (void);
char *procps_uptime_sprint_short (void);
Namespace Particulars
int procps_ns_get_id (const char *name);
const char *procps_ns_get_name (int id);
int procps_ns_read_pid (int pid, struct procps_ns *nsp);
Link with -lproc2.
DESCRIPTION
procps_cpu_count() returns the number of CPUs that are currently online
as sysconf(_SC_NPROCESSORS_ONLY) or an assumed 1.
procps_hertz_get() returns the number of clock ticks per second as
sysconf(_SC_CLK_TCK) or an assumed 100. Dividing tics by this value
yields seconds.
procps_pid_length() returns the maximum string length for a PID on the
system. For example, if the largest possible PID value on was 123, then
the length would be 3. If the file /proc/sys/kernel/pid_max is
unreadable, the value is assumed to be 5.
procps_linux_version() returns the current Linux version as an encoded
integer. On non-Linux systems that have an emulated proc filesystem
this function returns the version of the Linux emulation instead. The
version consists of three positive integers representing the major,
minor and patch levels. The following macros are provided for encoding
a given Linux version or separating out the components of the current
version.
LINUX_VERSION( major , minor , patch )
LINUX_VERSION_MAJOR( ver )
LINUX_VERSION_MINOR( ver )
LINUX_VERSION_PATCH( ver )
procps_loadavg() fetches the system load average and puts the 1, 5 and
15 minute averages into location(s) specified by any pointer which is
not NULL.
procps_uptime() returns uptime and/or idle seconds into location(s)
specified by any pointer which is not NULL. The sprint varieties
return a human-readable string in one of two forms.
HH:MM:SS up HH:MM, # users, load average: 1, 5, 15 MM averages
up HH, MM
procps_ns_get_id() returns the integer id (enum namespace_type) of the
namespace for the given namespace name.
procps_ns_get_name() returns the name of the namespace for the given id
(enum namespace_type).
procps_ns_read_pid() returns the inodes for the namespaces of the given
process in the procps_ns structure pointed to by nsp. Those inodes
will appear in the order proscribed by enum namespace_type.
enum namespace_type {
PROCPS_NS_CGROUP,
PROCPS_NS_IPC,
PROCPS_NS_MNT,
PROCPS_NS_NET,
PROCPS_NS_PID,
PROCPS_NS_TIME,
PROCPS_NS_USER,
PROCPS_NS_UTS
};
RETURN VALUE
Functions Returning an `int' or `long'
An error will be indicated by a negative number that is always the
inverse of some well known errno.h value.
Functions Returning an `address'
An error will be indicated by a NULL return pointer with the reason
found in the formal errno value.
FILES
/proc/loadavg
The raw values for load average.
/proc/sys/kernel/osrelease
Contains the release version of the Linux kernel or proc
filesystem.
/proc/sys/kernel/pid_max
Contains the value at which PIDs wrap around, one greater than
the maximum PID value.
/proc/uptime
The raw values for uptime and idle time.
/proc/<PID>/ns
contains the set of namespaces for a particular PID.
SEE ALSO
procps(3), procps_pids(3), proc(5).
libproc2 August 2022 PROCPS_MISC(3)
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