glibc/grp/grp.h

/* Copyright (C) 1991, 1992, 1995, 1996, 1997 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

/*
 *	POSIX Standard: 9.2.1 Group Database Access	<grp.h>
 */

#ifndef	_GRP_H
#define	_GRP_H	1

#include <features.h>

__BEGIN_DECLS

#include <bits/types.h>

#define __need_size_t
#include <stddef.h>


/* The group structure.	 */
struct group
  {
    char *gr_name;		/* Group name.	*/
    char *gr_passwd;		/* Password.	*/
    __gid_t gr_gid;		/* Group ID.	*/
    char **gr_mem;		/* Member list.	*/
  };


#if defined __USE_SVID || defined __USE_GNU
# define __need_FILE
# include <stdio.h>
#endif

#ifdef	__USE_GNU
/* Return a new stream open on the group file.  */
extern FILE *__grpopen __P ((void));

/* Read a group entry from STREAM, filling in G.
   Return the `struct group' of G if successful, NULL on failure.  */
extern struct group *__grpread __P ((FILE *__stream, __ptr_t __g));

/* Return a chunk of memory containing pre-initialized data for __grpread.  */
extern __ptr_t __grpalloc __P ((void));

/* Scan the group file, filling in G, until SELECTOR returns nonzero for an
   entry.  Return the `struct group' of G if successful, NULL on failure.  */
extern struct group *__grpscan __P ((__ptr_t *__p,
				     int (*__selector) (struct group *)));
#endif


#if defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN_EXTENDED
/* Rewind the group-file stream.  */
extern void setgrent __P ((void));

/* Close the group-file stream.  */
extern void endgrent __P ((void));

/* Read an entry from the group-file stream, opening it if necessary.  */
extern struct group *getgrent __P ((void));
#endif

#ifdef	__USE_SVID
/* Read a group entry from STREAM.  */
extern struct group *fgetgrent __P ((FILE *__stream));
#endif

/* Search for an entry with a matching group ID.  */
extern struct group *getgrgid __P ((__gid_t __gid));

/* Search for an entry with a matching group name.  */
extern struct group *getgrnam __P ((__const char *__name));

#if defined __USE_POSIX || defined __USE_MISC

# ifdef __USE_MISC
/* Reasonable value for the buffer sized used in the reentrant
   functions below.  But better use `sysconf'.  */
#  define NSS_BUFLEN_GROUP	1024
# endif

/* Reentrant versions of some of the functions above.

   PLEASE NOTE: the `getgrent_r' function is not (yet) standardized.
   The interface may change in later versions of this library.  But
   the interface is designed following the principals used for the
   other reentrant functions so the chances are good this is what the
   POSIX people would choose.  */

# if defined __USE_SVID || defined __USE_BSD || defined __USE_XOPEN_EXTENDED
extern int __getgrent_r __P ((struct group *__resultbuf, char *buffer,
			      size_t __buflen, struct group **__result));
extern int getgrent_r __P ((struct group *__resultbuf, char *buffer,
			    size_t __buflen, struct group **__result));
# endif

/* Search for an entry with a matching group ID.  */
extern int getgrgid_r __P ((__gid_t __gid, struct group *__resultbuf,
			    char *buffer, size_t __buflen,
			    struct group **__result));

/* Search for an entry with a matching group name.  */
extern int getgrnam_r __P ((__const char *__name, struct group *__resultbuf,
			    char *buffer, size_t __buflen,
			    struct group **__result));

# ifdef	__USE_SVID
/* Read a group entry from STREAM.  This function is not standardized
   an probably never will.  */
extern int __fgetgrent_r __P ((FILE * __stream, struct group *__resultbuf,
			       char *buffer, size_t __buflen,
			       struct group **__result));
extern int fgetgrent_r __P ((FILE * __stream, struct group *__resultbuf,
			     char *buffer, size_t __buflen,
			     struct group **__result));
# endif

#endif	/* POSIX or reentrant */


#ifdef	__USE_BSD

# define __need_size_t
# include <stddef.h>

/* Set the group set for the current user to GROUPS (N of them).  */
extern int setgroups __P ((size_t __n, __const __gid_t *__groups));

/* Initialize the group set for the current user
   by reading the group database and using all groups
   of which USER is a member.  Also include GROUP.  */
extern int initgroups __P ((__const char *__user, __gid_t __group));

#endif /* Use BSD.  */

__END_DECLS

#endif /* grp.h  */