fgetgrent(3) — Linux manual page

fgetgrent(3)            Library Functions Manual            fgetgrent(3)

NAME         top

       fgetgrent - get group file entry

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <stdio.h>
       #include <sys/types.h>
       #include <grp.h>

       struct group *fgetgrent(FILE *stream);

   Feature Test Macro Requirements for glibc (see
   feature_test_macros(7)):

       fgetgrent():
           Since glibc 2.19:
               _DEFAULT_SOURCE
           glibc 2.19 and earlier:
               _SVID_SOURCE

DESCRIPTION         top

       The fgetgrent() function returns a pointer to a structure
       containing the group information from the file referred to by
       stream.  The first time it is called it returns the first entry;
       thereafter, it returns successive entries.  The file referred to
       by stream must have the same format as /etc/group (see group(5)).

       The group structure is defined in <grp.h> as follows:

           struct group {
               char   *gr_name;        /* group name */
               char   *gr_passwd;      /* group password */
               gid_t   gr_gid;         /* group ID */
               char  **gr_mem;         /* NULL-terminated array of pointers
                                          to names of group members */
           };

RETURN VALUE         top

       The fgetgrent() function returns a pointer to a group structure,
       or NULL if there are no more entries or an error occurs.  In the
       event of an error, errno is set to indicate the error.

ERRORS         top

       ENOMEM Insufficient memory to allocate group structure.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).

       ┌─────────────────────┬───────────────┬──────────────────────────┐
       │Interface            │ Attribute     │ Value                    │
       ├─────────────────────┼───────────────┼──────────────────────────┤
       │fgetgrent()          │ Thread safety │ MT-Unsafe race:fgetgrent │
       └─────────────────────┴───────────────┴──────────────────────────┘

STANDARDS         top

       None.

HISTORY         top

       SVr4.

SEE ALSO         top

       endgrent(3), fgetgrent_r(3), fopen(3), getgrent(3), getgrgid(3),
       getgrnam(3), putgrent(3), setgrent(3), group(5)

Linux man-pages 6.04           2023-03-30                   fgetgrent(3)

Pages that refer to this page: getgrent(3),  getgrent_r(3),  getgrnam(3),  putgrent(3)

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