$schemamarkup = get_post_meta(get_the_ID(), 'schemamarkup', true); if(!empty($schemamarkup)) { echo $schemamarkup; }

How to Enable Perl CGI on Red-Hat Linux Based Systems

Perl CGI Quick Start for RHEL

The Linked Tutorials Show you Step-by-Step How to Getting-Started with Perl CGI Web Scripts on Red Hat Enterprise Linux 6.x/7.x/8.x GNU/Linux Based OSes.

CGI.pm is a large and widely used Perl module for Programming Common Gateway Interface (CGI) web applications, providing a consistent API for receiving and processing user input.

Perl CGI Quick Start for Red-Hat Linux - Featured

Enabling Perl CGI on EL