INITGROUPS(3)

NAME
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 to indicate the error.

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).
Interface | Attribute | Value
 | Thread safety | MT-Safe locale

CONFORMING TO
SVr4, 4.3BSD.

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

COLOPHON
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