42.3 Why Changing TERM Sometimes Doesn't Work

The use of tset to set the TERMCAP environmentvariable (5.4) can cause problems for new users who do not understand it completely. For example, as long as the TERMCAP variable is not set, programs look by default in /etc/termcap. However, once the TERMCAP variable contains the actual termcap entry, changing the value of TERM will no longer have any effect on a program like vi.

If you set the value of TERM correctly but vi or other programs that depend on TERM still do not seem to work, check (6.1) that TERMCAP is not set to the actual termcap entry (41.11). You can clear this condition with the command:

% unsetenv TERMCAP

or:

$ TERMCAP=

or:

$ unset TERMCAP        (newer Bourne shells)