Perlaccess : Tutorials : File and Directory
Creating New Directories (12.3)
by Jacob A. Wheeler
http://www.bigresources.com

Below is how you create a new Directory:

mkdir NAME, MODE
NAME = Directory Name
MODE = Directory Permission (eg: 655,755,777)

Example:
#!/usr/bin/perl
$new_dir = "Bob"
$perm = 755;
makeDir();
sub makeDir {
mkdir ($new_dir,$perm) or "Error making Directory ($new_dir)\n";
exit();
}