INITGROUPS

initgroups − initialize the supplementary group access list

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

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

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 initgroups() function returns 0 on success, or −1 if an error occurs.

EPERM

The calling process does not have sufficient privileges.

ENOMEM

Insufficient memory to allocate group information structure.

/etc/group

group database file

SVID 3, BSD 4.3

getgroups(2), setgroups(2)