getpw(3) Linux Man Page - System Grab Bag

Name

getpw - reconstruct password line entry

Library

Standard C library ( libc ", " -lc )

Synopsis

"#define(7)_GNU_SOURCE" "             /* See feature_test_macros */" #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 " ENOENTNo 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). allbox; lbx lb lb T{ getpw()

Interface	Attribute	Value
T}	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).