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ENDGRENT(P)			    POSIX Programmer's Manual			      ENDGRENT(P)

NAME
       endgrent, getgrent, setgrent - group database entry functions

SYNOPSIS
       #include <grp.h>

       void endgrent(void);
       struct group *getgrent(void);
       void setgrent(void);

DESCRIPTION
       The  getgrent()	function  shall return a pointer to a structure containing the broken-out
       fields of an entry in the group database. When first called,  getgrent()  shall	return	a
       pointer to a group structure containing the first entry in the group database. Thereafter,
       it shall return a pointer to a group structure containing the next group structure in  the
       group database, so successive calls may be used to search the entire database.

       An  implementation that provides extended security controls may impose further implementa-
       tion-defined restrictions on accessing the group database. In particular, the  system  may
       deny  the  existence  of  some or all of the group database entries associated with groups
       other than those groups associated with the caller and may omit users other than the call-
       er from the list of members of groups in database entries that are returned.

       The setgrent() function shall rewind the group database to allow repeated searches.

       The  endgrent() function may be called to close the group database when processing is com-
       plete.

       These functions need not be reentrant. A function that is not required to be reentrant  is
       not required to be thread-safe.

RETURN VALUE
       When  first  called, getgrent() shall return a pointer to the first group structure in the
       group database. Upon subsequent calls it shall return the  next	group  structure  in  the
       group  database.  The getgrent() function shall return a null pointer on end-of-file or an
       error and errno may be set to indicate the error.

       The return value may point to a static area which is overwritten by a subsequent  call  to
       getgrgid(), getgrnam(), or getgrent().

ERRORS
       The getgrent() function may fail if:

       EINTR  A signal was caught during the operation.

       EIO    An I/O error has occurred.

       EMFILE {OPEN_MAX} file descriptors are currently open in the calling process.

       ENFILE The maximum allowable number of files is currently open in the system.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       These  functions  are  provided	due  to their historical usage. Applications should avoid
       dependencies on fields in the group database, whether the database is a	single	file,  or
       where  in  the file system name space the database resides. Applications should use getgr-
       nam() and getgrgid() whenever possible because it avoids these dependencies.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       getgrgid() , getgrnam() , getlogin()  ,	getpwent()  ,  the  Base  Definitions  volume  of
       IEEE Std 1003.1-2001, <grp.h>

COPYRIGHT
       Portions  of  this  text  are  reprinted  and  reproduced in electronic form from IEEE Std
       1003.1, 2003 Edition, Standard for Information Technology  --  Portable	Operating  System
       Interface  (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 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 orig-
       inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group			       2003				      ENDGRENT(P)
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