INITGROUPS(3) |
Library Functions Manual |
INITGROUPS(3) |
NAME
initgroups — initialize supplementary group IDs
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
int
initgroups(const char *name, gid_t basegid);
DESCRIPTION
The
initgroups() function uses the
getgrouplist(3) function to calculate the supplementary group IDs for the user specified in
name. This group list is then set up for the current process using
setgroups(2). The
basegid is automatically included in the group list. Typically this value is given as the group number from the password file.
If the groups database lists more than NGROUPS groups for name (including one for basegid), the later groups are ignored.
RETURN VALUES
The initgroups() function returns -1 if it was not invoked by the super-user.
HISTORY
The initgroups() function appeared in 4.2BSD.
BUGS
The
getgrouplist() function called by
initgroups() uses the routines based on
getgrent(3). If the invoking program uses any of these routines, the group structure will be overwritten in the call to
initgroups().