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

How to Install Linux Headers Without Internet on Ubuntu Gnu/Linux Distro

GNU/Linux Ubuntu Headers Offline Installation

Hi! This tutorial will guide you step-by-step on How to Download and Install Offline Linux Kernel Headers for Ubuntu GNU/Linux Computers.

And the Ubuntu linux-headers Package provide the Headers needed to compile Modules for the Linux Kernel.

Most noteworthy: to achieve this Setup you simply need any Online Computer with a Browser and a USB Stick to Copy the downloaded Package.

But if you dispose of an Android Mobile Phone with Internet Acces, then an Easier Solution should be of using it! See: Internet Connection USB Tethering Guide.

How to Install Linux Headers without Internet on Ubuntu GNU/Linux Distro - Featured

GNU/Linux Ubuntu Kernel Headers Offline Installation Guide