| NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | FILES | CONFORMING TO | SEE ALSO | COLOPHON | The Linux Programming Interface |
GETPWENT(3) Linux Programmer's Manual GETPWENT(3)
getpwent, setpwent, endpwent - get password file entry
#include <sys/types.h>
#include <pwd.h>
struct passwd *getpwent(void);
void setpwent(void);
void endpwent(void);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
getpwent(), setpwent(), endpwent():
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 500 ||
_XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED
The getpwent() function returns a pointer to a structure containing the
broken-out fields of a record from the password database (e.g., the local
password file /etc/passwd, NIS, and LDAP). The first time getpwent() is
called, it returns the first entry; thereafter, it returns successive entries.
The setpwent() function rewinds to the beginning of the password database.
The endpwent() function is used to close the password database after all
processing has been performed.
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).
The getpwent() function returns a pointer to a passwd structure, or NULL if
there are no more entries or an error occurs. If an error occurs, errno is
set appropriately. If one wants to check errno after the call, it should be
set to zero before the call.
The return value may point to a static area, and may be overwritten by
subsequent calls to getpwent(), getpwnam(3), or getpwuid(3). (Do not pass the
returned pointer to free(3).)
EINTR A signal was caught.
EIO I/O error.
EMFILE The maximum number (OPEN_MAX) of files was open already in the calling
process.
ENFILE The maximum number of files was open already in the system.
ENOMEM Insufficient memory to allocate passwd structure.
ERANGE Insufficient buffer space supplied.
/etc/passwd
local password database file
SVr4, 4.3BSD, POSIX.1-2001. The pw_gecos field is not specified in POSIX, but
is present on most implementations.
fgetpwent(3), getpw(3), getpwent_r(3), getpwnam(3), getpwuid(3), putpwent(3),
passwd(5)
This page is part of release 3.32 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can be found
at http://www.kernel.org/doc/man-pages/.
GNU 2010-10-21 GETPWENT(3)
HTML rendering created 2010-12-03 by Michael Kerrisk, author of The Linux Programming Interface