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GETGROUPLIST(3)            Library Functions Manual            GETGROUPLIST(3)

NAME
     getgrouplist, getgroupmembership - calculate group access list

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #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);

DESCRIPTION
     The 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.

RETURN VALUES
     The 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.

FILES
     /etc/group  group membership list

SEE ALSO
     setgroups(2), initgroups(3), group(5)

HISTORY
     The getgrouplist() function first appeared in 4.4BSD.  The
     getgroupmembership() function first appeared in NetBSD 3.0 to address an
     API deficiency in getgrouplist().

BUGS
     The 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().

NetBSD 10.99                    January 6, 2005                   NetBSD 10.99