As I have multiple cgi files, do I need to copy-paste that function in each file or is there any way to keep that function in separate file and use it, if possible how?

This sort of code re-use is performed in Perl using modules. See Simple Module Tutorial for how to create and use a module for such a purpose. There are other, similar guides for Creating and Distributing Modules in our Tutorials section.

The traditional approach to keeping an often-used function in a file is named a "module". You have already been shown the links to the modules and also links on how to install modules into a Perl.

Most likely, use lib will be enough, but a look at Yes, even you can use CPAN and/or local::lib won't hurt either.

"Thanks..."

My pleasure. Next step: Go over that bridge named "module" - as some fellow monks mentioned already.

Like this, less or more:

package YourModule;

use strict;
use warnings;
use Exporter qw(import);

our ( $VERSION, @EXPORT_OK );

$VERSION   = 1.00;

@EXPORT_OK = qw(from_json);

sub from_json {
   # stuff... 
}

1;
[download]

See also Re: How to parse the logs in a generic manner

Regards, Karl

Hi, Done. Thank you everyone for help. :D