2010-04-06

screen, tset, & emacs

Have had an issue w/ using emacs and screen together under Bash on a CentOS Linux host.

Problem

The problem manifests in two ways:

  1. font-lock-mode does not show in color, or in a limited subset of colors
  2. the Backspace key sends ^H but Emacs recognizes it as the "Help" invocation, and starts up the Help system

These problems have been showing up under screen but not when Emacs is started outside screen in the normal Bash shell.

Changing the TERM value and/or the Backspace in either or both of the terminal emulator software (PuTTY) did not fix the problem.

Setting the value of the TERM environment value in Bash had no apparent effect.

The Fix

Use tset to set the backspace character in the Bash shell before screen is started.

tset -e ^H

This works when TERM=vt102 in the Bash environment, and 'VT100+' is checked for the terminal type in PuTTY. Other term types may vary.

Note that for some reason the font-lock-mode problem went away, too.