perlquestion supriyoch_2008 <p>Hi PerlMonks,</p> <p>I am interested to create a folder B in D drive of computer and then save results in a text file (Result_File.txt) inside B folder using perl. For this I have written the following script p5.pl but the cmd has shown an error. I am at my wit's end to find a solution. I searched in perldoc but couldn't find the code applicable in my case. I can't make out what the technical term perlIO layer really means in the error message in cmd. May I request PerlMonks to provide suggestions in this matter?</p> <p>Here goes the script p5.pl:</p> <code>#!/usr/bin/perl use warnings; use strict; my $a=9; my $b=5; my $c=$a*$b; ## Create the folder B in D drive & Save results as Result_File.txt # within B folder: my $output="Result_File.txt"; open (my $fh,">D://B/",$output) or die"Cannot open file'$output'.\n"; # Line 10 print $fh "\n WELCOME! Product of 9 & 5= $c\n\n"; close $output; exit;</code> <p>Here goes the error message in cmd screen:</p> <code>C:\Users\x\Desktop>p5.pl Unknown PerlIO layer "D" at C:\Users\x\Desktop\p5.pl line 10. Cannot open file'Result_File.txt'.</code>