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 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 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
IEEE Std
1003.1-1990 (“POSIX.1”).
HISTORY
The
getgroups() function call appeared in
4.2BSD.