Re: [PATCH] difftool: always honor "command not found" exit code

From: Tom Tanner (BLOOMBERG/ LONDON) <ttanner2@bloomberg.net>
Date: Aug 15, 2016, 10:38 UTC
Message-ID: <57B19B9F0205070000390238_0_29566@p057>

Would it be possible to also treat signals (128 and above) as 'special' values as well (as I've seen some merge tools self destruct like that from time to time)

----- Original Message -----
From: gitster@pobox.com
To: john@keeping.me.uk
Cc: Tom Tanner (BLOOMBERG/ LONDON), davvid@gmail.com, git@vger.kernel.org
At: 08/14/16 04:21:18

John Keeping <john@keeping.me.uk> writes:

Show 13 quoted lines

> At the moment difftool's "trust exit code" logic always suppresses the
> exit status of the diff utility we invoke.  This is useful because we
> don't want to exit just because diff returned "1" because the files
> differ, but it's confusing if the shell returns an error because the
> selected diff utility is not found.
>
> POSIX specifies 127 as the exit status for "command not found" and 126
> for "command found but is not executable" [1] and at least bash and dash
> follow this specification, while diff utilities generally use "1" for
> the exit status we want to ignore.
>
> Handle 126 and 127 as special values, assuming that they always mean
> that the command could not be executed.

Sounds like a reasonable thing to do.  Will queue; thanks.