netbsd man page for getgroups

GETGROUPS(2)						      BSD System Calls Manual						      GETGROUPS(2)

NAME
     getgroups -- get group access list

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <unistd.h>

     int
     getgroups(int gidsetlen, gid_t *gidset);

DESCRIPTION
     getgroups() gets the current group access list of the current user process and stores it in the array gidset.  The parameter gidsetlen indi-
     cates the number of entries that may be placed in gidset.	getgroups() returns the actual number of groups returned in gidset.  No more than
     {NGROUPS_MAX} will ever be returned.  If gidsetlen is 0, getgroups() returns the number of groups without modifying the gidset array.

     This system call only returns the secondary groups.

RETURN VALUES
     A successful call returns the number of groups in the group set.  A value of -1 indicates that an error occurred, and the error code is
     stored in the global variable errno.

ERRORS
     The possible errors for getgroups() are:

     [EINVAL]		The argument gidsetlen is non-zero and is smaller than the number of groups in the group set.

     [EFAULT]		The argument gidset specifies an invalid address.

SEE ALSO
     getegid(2), getgid(2), setgroups(2), initgroups(3)

STANDARDS
     The getgroups() function conforms to ISO/IEC 9945-1:1990 (``POSIX.1'').

HISTORY
     The getgroups() function call appeared in 4.2BSD.

BSD
								  October 7, 2006							       BSD