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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | FILES | CONFORMING TO | SEE ALSO | COLOPHON


GETPWENT(3)                   Linux Programmer's Manual                   GETPWENT(3)

NAME         top

       getpwent, setpwent, endpwent - get password file entry

SYNOPSIS         top

       #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

DESCRIPTION         top

       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 it 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;      /* real name */
               char   *pw_dir;        /* home directory */
               char   *pw_shell;      /* shell program */
           };

RETURN VALUE         top

       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).)

ERRORS         top

       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.

FILES         top

       /etc/passwd
              local password database file

CONFORMING TO         top

       SVr4, 4.3BSD, POSIX.1-2001.

SEE ALSO         top

       fgetpwent(3), getpw(3), getpwent_r(3), getpwnam(3), getpwuid(3), putpwent(3),
       passwd(5)

COLOPHON         top

       This page is part of release 3.23 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                                   2009-03-30                          GETPWENT(3)