getpw

Section: C Library Functions (3)
Updated: 2022-12-15
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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 attributes(7).

Interface	Attribute	Value
getpw()	Thread safety	MT-Safe locale

STANDARDS

SVr2.

BUGS

The getpw() function is dangerous as it may overflow the provided buffer buf. It is obsoleted by getpwuid(3).

This document was created by man2html, using the manual pages.
Time: 13:14:02 GMT, April 26, 2024