use strict;
use warnings;
use Data::Dumper;

my %userlist = ();

while (my $line = <DATA>) {
   chomp($line);
   my %row = ();
   @row{qw/user locked uid gid comment home shell/} = split /:/, $line;
   $userlist{$row{user}} = \%row;
}

while ( 1 ) {
   print "\nWelcher Benutzer soll angezeigt werden?  ";
   chomp(my $user = <STDIN>);
   if ($userlist{$user}) {
      print "\nDaten des Benutzers $user aus passwd :";
      print "\nUser-ID:   $userlist{$user}{uid}";
      print "\nGroup-ID:  $userlist{$user}{gid}";
      print "\nKommentar: $userlist{$user}{comment}";
      print "\nHome-Verz: $userlist{$user}{home}";
      print "\nShell:     $userlist{$user}{shell}\n";
   } else {
      print "Diesen Benutzer gibt es nicht!\n";
   }
}

__END__
root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/bin/sh
bin:x:2:2:bin:/bin:/bin/sh
sys:x:3:3:sys:/dev:/bin/sh