rand()

How to generate a random string and append to filenames you want to generate and make them unique.

my $randstring = &gen_rand($randlength);
sub gen_rand()
{

     my @chars = ('a'..'z','A'..'Z','0'..'9','_');
     my $randstring;
     my $length_rand = shift;

     foreach (0..$length_rand)
             {
                     $randstring .= $chars[rand @chars];
             }
     return $randstring;

}