open (OUTFILE, ">$basedir/$fileName");

##</code><code>##

open (OUTFILE, ">$basedir/$subdir/$fileName");

##</code><code>##

mkdir("$basedir/$subdir") unless -d "$basedir/$subdir";
open (OUTFILE, ">$basedir/$subdir/$fileName") 
   or die "Could not open $basedir/$subdir/$fileName: $!";