use strict;
use GDBM_File;

my $nis_domain="your_domain";
#location of nis files
my $passwd_byuid="/var/yp/".$nis_domain."/passwd.byuid"; 
my %nis;# informations from nis map
my @delete; # users not in the nis map
mu @user_info; # informations from /etc/passwd

## get the users from /etc/passwd ###
open (fd, '/etc/passwd') or die "can't access /etc/passwd";
my @CONTENTS = <fd>;
close (fd);

tie (%nis,'GDBM_File',$passwd_byname,0,0) or die "Can't access NIS pas
+swd.byname";

foreach $line (@CONTENTS) {
  @user_info=split (/:/,$line);
  if (substr($user_info[0],0,1) eq "+") {
    $user_info[0]=~ s/\+//;
    if (!$nis{'$user_info[0]'}) {
      push @delete,$user_info[0];
      }
  }
}
untie (%nis);
[download]

Anono-monk,

What is your criteria for skipping an entry? You have root, and johnny marked as skip, but you didnt give a reason that it should be skipped.

Otherwise, here is a theoretical solution

First, open your /etc/passwd file, and read it to an array

  open (fd, '/etc/passwd') or die $!;
  my @CONTENTS = <fd>;
  close (fd);
[download]

Now that that is done, get each entry except for root, and compare it to the NIS one

  sub ypMatchit
  {#This does the most work
    # I don't know if you want to add root and johnny
    # to your new file or not. If you do want them to
    # be added, then change the next trwo undef's you 
    # see to be '0';
    return undef if ($_ && 'root');
    return undef if ((<i>rules for skipping johnny are enforced</i>));
    my $Final = ypmatch($_);
    
    #add any other processing you want to do here
    return 0 if ($Final = (SUCCESS));
    return undef;
  }
  my @FINAL = ();
  foreach my $CurrentEntry ( @CONTENTS )
  {
    push @FINAL, $CurrentEntry if( defined(ypMatchit($CurrentEntry)));
  }
[download]

Now write the final thing out to a file

  open (FD, '/etc/newPasswd') or die $!;
  foreach (@FINAL) { print FD $_; }
  close (FD);
[download]

This is all theory by the way, but I think it is a good start (I did somthing similiar several months ago, and this methodology worked.

HTH - Kristofer

See getpwent and friends for reading the local user data. Watch out for system users like nobody and daemon.

After Compline,
Zaxo

I don't think it works : getpwent will read the local files AND the nis map. (I've already had this problem with getgrent).