initgroups - initialize the supplementary group access list
#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 appropriately.
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 |
initgroups() | Thread safety | MT-Safe locale |
SVr4, 4.3BSD.
getgroups(2), setgroups(2), credentials(7)
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