printing on thermal printer with Linux

Apparently thermal printers, like dot-matrix printers, also use certain escape codes and the rest of the text is treated like "Generic Text". This experts exchange page says at the very bottom, it may be better to have the code directly in the app. And this MSDN forum post links to a pdf with escape codes. PB used the OpenBravo forum for help.

From PB's private blog,

Using EPSON TM-T88IV parallel port on ubuntu 9.04
In openbravo configuration set the printer as epson - File - /dev/lp0
To make the printer accessible by a normal user set the permissions:
sudo chmod a+rw /dev/lp0
Note: These settings are lost on reboot.
To set these permissions on boot, I added the following line in /etc/rc.local (in Ubuntu 9.04) before the exit command
# For parallel port printers add:
chmod a+rw /dev/lp0
# For USB printers add:
chmod a+rw /dev/usblp0