getpw(3) Library Functions Manual getpw(3)
NAME
getpw - reconstruct password line entry
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <sys/types.h>
#include <pwd.h>
[[deprecated]] int getpw(uid_t uid, char *buf);
DESCRIPTION
The getpw() function reconstructs the password line entry for the given
user ID uid in the buffer buf. The returned buffer contains a line of
format
name:passwd:uid:gid:gecos:dir:shell
The passwd structure is defined in <pwd.h> as follows:
struct passwd {
char *pw_name; /* username */
char *pw_passwd; /* user password */
uid_t pw_uid; /* user ID */
gid_t pw_gid; /* group ID */
char *pw_gecos; /* user information */
char *pw_dir; /* home directory */
char *pw_shell; /* shell program */
};
For more information about the fields of this structure, see passwd(5).
RETURN VALUE
The getpw() function returns 0 on success; on error, it returns -1, and
errno is set to indicate the error.
If uid is not found in the password database, getpw() returns -1, sets
errno to 0, and leaves buf unchanged.
ERRORS
0 or ENOENT
No user corresponding to uid.
EINVAL buf is NULL.
ENOMEM Insufficient memory to allocate passwd structure.
FILES
/etc/passwd
password database file
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌────────────────────────────────────┬───────────────┬────────────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────┼───────────────┼────────────────┤
│ getpw() │ Thread safety │ MT-Safe locale │
└────────────────────────────────────┴───────────────┴────────────────┘
STANDARDS
None.
HISTORY
SVr2.
BUGS
The getpw() function is dangerous as it may overflow the provided
buffer buf. It is obsoleted by getpwuid(3).
SEE ALSO
endpwent(3), fgetpwent(3), getpwent(3), getpwnam(3), getpwuid(3), putp-
went(3), setpwent(3), passwd(5)
Linux man-pages 6.7 2023-10-31 getpw(3)
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