| GETGROUPLIST(3) | Library Functions Manual | GETGROUPLIST(3) | 
getgrouplist, getgroupmembership
  —
#include <unistd.h>
int
  
  getgrouplist(const
    char *name, gid_t
    basegid, gid_t
    *groups, int
    *ngroups);
int
  
  getgroupmembership(const
    char *name, gid_t
    basegid, gid_t
    *groups, int
    maxgrp, int
    *ngroups);
getgrouplist() and
  getgroupmembership() functions read through the group
  database and calculate the group access list for the user specified in
  name. The basegid is automatically
  included in the groups list. Typically this value is given as the group number
  from the password database.
The resulting group list is returned in the integer array pointed to by groups.
For getgrouplist(), the caller specifies
    the size of the groups array in the integer pointed to
    by ngroups.
For getgroupmembership(), the caller
    specifies the size of the groups array in
    maxgrp.
The actual number of groups found is returned in ngroups.
Duplicate group ids will be suppressed from the result.
getgrouplist() and
  getgroupmembership() functions return 0 if successful,
  and return -1 if the size of the group list is too small to hold all the
  user's groups. In the latter case, the groups array will
  be filled with as many groups as will fit and ngroups
  will contain the total number of groups found.
getgrouplist() function first appeared in
  4.4BSD. The
  getgroupmembership() function first appeared in
  NetBSD 3.0 to address an API deficiency in
  getgrouplist().
getgrouplist() function 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 getgrouplist().
| January 6, 2005 | NetBSD 10.0 |