Terminal Settings

Vim can need some prodding to work well in some terminals. This page lists some settings which I’ve found to work well on my Linux set-up. These are all included in the sample .vimrc configuration file.

For various historical reasons, it seems to be pretty random what effect <BkSpc> and <Del> will have in different Unix terminals, programs, modes, etc. To make these keys behave properly in XTerm, Gnome Terminal, Konsole, and KVT, these settings are needed:

execute 'set t_kb=' . nr2char(8)
fixdel

Note these lines can make things worse if used in another terminal (such as RXVT) or when running Vim with the gui. See below for how to prevent this happening.

When using some versions of Gnome Terminal, a completely spurious “c” character gets output whenever Vim is run (though usually it isn’t seen until exiting Vim). This stops it:

set t_RV=

It is possible to make Vim automatically do The Right Thing for the terminal in which it has been run. All of the above-mentioned terminals claim to have “xterm” in their names, so it is easy to test for the term option including this; whenever Vim’s gui is being used term will be something else, and none of these settings will be inadvertently triggered.

Distinguishing between these terminals is harder. Gnome Terminal helpfully sets $COLORTERM to gnome-terminal, but it’s only possible to guess at it being one of t’others if $COLORTERM is empty. Fortunately RXVT (for which no prodding is wanted) also sets $COLORTERM so doesn’t get trapped by this, but it’s possible that there are other terminals out there that also have an empty $COLORTERM yet don’t want the same settings as XTerm et al. Here’s the code:

if &term =~ 'xterm'
  if $COLORTERM == 'gnome-terminal'
    execute 'set t_kb=' . nr2char(8)
    fixdel
    set t_RV=
  elseif $COLORTERM == ''
    execute 'set t_kb=' . nr2char(8)
    fixdel
  endif
endif

Konsole actually sets $COLORTERM to an empty string, but XTerm and KVT don’t touch it. So if one of those two is started from within a terminal that does set $COLORTERM, then it will be wrongly identified as the ‘parent’ terminal.