initgroups man page

initgroups — initialize the supplementary group access list

Synopsis

#include <sys/types.h>
#include <grp.h>

int initgroups(const char *user, gid_t group);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

initgroups():
Since glibc 2.19:
_DEFAULT_SOURCE
Glibc 2.19 and earlier:
_BSD_SOURCE

Description

The initgroups() function initializes the group access list by reading the group database /etc/group and using all groups of which user is a member. The additional group group is also added to the list.

The user argument must be non-NULL.

Return Value

The initgroups() function returns 0 on success. On error, -1 is returned, and errno is set appropriately.

Errors

ENOMEM
Insufficient memory to allocate group information structure.
EPERM
The calling process has insufficient privilege. See the underlying system call setgroups(2).

Files

/etc/group		group database file

Attributes

For an explanation of the terms used in this section, see attributes(7).

InterfaceAttributeValue
initgroups()Thread safetyMT-Safe locale

Conforming to

SVr4, 4.3BSD.

See Also

getgroups(2), setgroups(2), credentials(7)

Colophon

This page is part of release 4.08 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.

Referenced By

credentials(7), getgroups(2), group(5), nss(5), slapd(8).

2016-03-15 GNU Linux Programmer's Manual