<code perl|f password-gen.pl>
#!/usr/bin/perl

# code released by David Douthitt into the public domain

use Getopt::Long;

Getopt::Long::Configure('bundling');
GetOptions( 'l=i' => \$opt_l,
            'p=s' => \$opt_p,
            'm=i' => \$opt_m );

$pat{"ext"} = "[[:alnum:][:punct:]]";
$pat{"alnum"} = "[[:alnum:]]";
$pat{"alpha"} = "[[:alpha:]]";
$pat{"simple"} = "[a-km-z2-9]";
$pat{"normal"} = "[a-km-z2-9A-HJ-NPR-Z]";

if (defined($opt_p)) {
   if (defined($pat{$opt_p})) {
      $pat = $pat{$opt_p};
   } else {
      print "undefined pattern!\n";
      exit(1);
   }
} else {
   $pat = $pat{"normal"};
}

$max = (defined($opt_m) ? $opt_m : 1000);
$len = (defined($opt_l) ? $opt_l : 6);

$x = $len;

for $i (0..$max) {
   $c = chr(int(rand(255)));
   if ($c =~ /$pat/o) {
      $s .= $c;
      if (--$x == 0) {
         print "$s\n";
         $x = $len;
         $s = "";
      }
   }
}
</code>