NAME
getgroups —
get group access list
LIBRARY
library “libc”
SYNOPSIS
#include
<sys/types.h>
#include <unistd.h>
int
getgroups(int
gidsetlen, gid_t
*gidset);
DESCRIPTION
Getgroups()
gets the current group access list of the user process and stores it in the
array gidset. The parameter
gidsetlen indicates 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 zero,
getgroups()
returns the number of supplementary group IDs associated with the calling
process without modifying the array pointed to by
gidset.
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 ALSO
HISTORY
The getgroups() function call appeared in
4.2BSD.