initgroups - initialize the supplementary group access list
Standard C library (libc
, -lc
)
#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
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.
The initgroups() function returns 0 on success. On
error, -1 is returned, and errno
is set to indicate the
error.
Insufficient memory to allocate group information structure.
The calling process has insufficient privilege. See the underlying system call setgroups(2).
/etc/group
group database file
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
Thread safety | MT-Safe locale |
None.
SVr4, 4.3BSD.
getgroups(2), setgroups(2), credentials(7)