PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of
       this interface may differ (consult the corresponding Linux  manual  page  for  details  of
       Linux behavior), or the interface may not be implemented on Linux.

NAME

       grp.h — group structure

SYNOPSIS

       #include <grp.h>

DESCRIPTION

       The  <grp.h>  header  shall declare the group structure, which shall include the following
       members:

           char   *gr_name The name of the group.
           gid_t   gr_gid  Numerical group ID.
           char  **gr_mem  Pointer to a null-terminated array of character
                           pointers to member names.

       The <grp.h> header shall define the gid_t and size_t types as described in <sys/types.h>.

       The following shall be declared as functions and may also be defined as  macros.  Function
       prototypes shall be provided.

           void           endgrent(void);
           struct group  *getgrent(void);
           struct group  *getgrgid(gid_t);
           int            getgrgid_r(gid_t, struct group *, char *,
                              size_t, struct group **);
           struct group  *getgrnam(const char *);
           int            getgrnam_r(const char *, struct group *, char *,
                              size_t , struct group **);
           void           setgrent(void);

       The following sections are informative.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       <sys_types.h>

       The System Interfaces volume of POSIX.1‐2017, endgrent(), getgrgid(), getgrnam()

COPYRIGHT

       Portions  of  this  text  are  reprinted  and  reproduced in electronic form from IEEE Std
       1003.1-2017, Standard for Information Technology -- Portable  Operating  System  Interface
       (POSIX),  The  Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by
       the Institute of Electrical and Electronics Engineers, Inc and The  Open  Group.   In  the
       event  of  any  discrepancy  between this version and the original IEEE and The Open Group
       Standard, the original IEEE and The Open Group  Standard  is  the  referee  document.  The
       original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

       Any  typographical  or  formatting errors that appear in this page are most likely to have
       been introduced during the conversion of the source files to man page  format.  To  report
       such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .