Hi PerlMonks,

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?

Here goes the script p5.pl:

#!/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;
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Here goes the error message in cmd screen:

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'.
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