GETGROUPS(2) BSD System Calls Manual GETGROUPS(2)NAMEgetgroups — get group access list
SYNOPSIS
#include <sys/param.h>
#include <sys/types.h>
#include <unistd.h>
int
getgroups(int gidsetlen, gid_t *gidset);
DESCRIPTIONGetgroups() 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.
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 smaller than the number of
groups in the group set.
[EFAULT] The argument gidset specifies an invalid address.
SEE ALSOsetgroups(2), initgroups(3)HISTORY
The getgroups() function call appeared in 4.2BSD.
4.2 Berkeley Distribution April 16, 1994 4.2 Berkeley Distribution