To avoid duplicate checks during the run of a program, I would optimize by making $counter a state variable

The modern perl way 

use feature qw/ state /;
state $counter = 1;

[download]

Or the old way, with a closure 

 BEGIN {
    my $counter = 1;
    sub DirPP {
        use Errno qw/ EACCES /; # permission denied
        my $word    = "site";
        my $name ;
        my $made = 0;
        while(1){
            $name = sprintf '%s%3d', $word, $counter;
            last if not $made = mkdir $name, 0755 ;
            die $! if $! == EACCES;
        }
        return $name if $made;
        return;
    }
}

[download]

In reply to Re^2: getting a while loop to terminate by Anonymous Monk
in thread getting a while loop to terminate by Aldebaran

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