configure: error: xml2-config not found. Please check your libxml2 installation.

I’m using Debian and it showed that I had libxml2 installed (and it was the latest version).

It turns out that the latest stable version of libxml2 doesn’t include a file named xml2-config. I suppose I could have linked that file to the config file that the stable version of libxml2 uses, but the easy fix is to just install the newer development version of libxml2 using the following command:

apt-get install libxml2-dev

That’s all I needed!

chmod 666 /dev/null

This solved the problem.

I was still having trouble with some shell accounts, though, because no users could access screen (virtual terminals). The error message was that no PTYs were available. I solved this problem by giving these users access to the /dev/ptmx directory. This directory was initially only readable, writable, and executable by root, but I made it so that anyone in the admin group could read write and execute this directory.

chown root:adm /dev/ptmx

chmod 770 /dev/ptmx

If you want any user to be able to use screen, you will have to do this:

chmod 777 /dev/ptmx