ENDGRENT(3P)						     POSIX Programmer's Manual						      ENDGRENT(3P)

PROLOG

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

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 implementation-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 caller 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 complete.

       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 getgrnam() and get-
       grgid() 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 Technol-
       ogy -- 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 original Standard can be obtained
       online at http://www.opengroup.org/unix/online.html .

IEEE
/The Open Group						       2003							      ENDGRENT(3P)