slave: unset TERM_PROGRAM{,_VERSION}

Foot’s policy is to not set environment variables that identifies
it (except the well-known and established `TERM` variable).

We encourage applications to use terminfo to determine capabilities,
or terminal queries, when available. Or, at least use terminal queries
to detect the terminal and its version.

Setting environment variables is a bad idea since they are inherited
by all applications started by the terminal (which is the whole
point). But, this includes other terminal emulators, making it very
possible a terminal emulator gets mis-detected just because it was
started from another terminal.

Since there are a couple of terminal emulators that _do_ set
TERM_PROGRAM and TERM_PROGRAM_VERSION, unset these environment
variables to avoid being misdetected.

Closes #1349
This commit is contained in:
Daniel Eklöf 2023-05-12 14:55:55 +02:00
parent d2f81443f1
commit a2f765b72a
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5 changed files with 4 additions and 27 deletions

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@ -158,17 +158,6 @@ terminfo entries manually, by copying *foot* and *foot-direct* to
This variable is set to *truecolor*, to indicate to client
applications that 24-bit RGB colors are supported.
*TERM_PROGRAM*
Always set to *foot*. This can be used by client applications to
check which terminal is in use, but with the caveat that it may
have been inherited from a parent process in other terminals that
aren't known to set the variable.
*TERM_PROGRAM_VERSION*
Set to the foot version string, in the format _major_*.*_minor_*.*_patch_
or _major_*.*_minor_*.*_patch_*-*_revision_*-\g*_commit_ for inter-release
builds. The same caveat as for *TERM_PROGRAM* applies.
In addition to the variables listed above, custom environment
variables may be defined in *foot.ini*(5).