bug#66338: 30.0.50; grep-commnd set and using an old fish results in empty Copyright files

[Alex Schroeder via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

Of course. From my point of view this is not a question of how to fix it. My main problem is that it took me so long to discover what the problem was.

-- 
Typed on a tiny keyboard. Sorry for being terse.

> On 5 Oct 2023, at 12:27, Michael Albinus <michael.albinus@gmx.de> wrote:
> 
> Alex Schroeder via "Bug reports for GNU Emacs, the Swiss army knife of
> text editors" <bug-gnu-emacs@gnu.org> writes:
> 
> Hi Alex,
> 
>>> So Emacs expects this variable to point to a shell that Emacs can use
>>> to run programs, not your interactive shell.  If you want a different
>>> shell to be used in interactive shell sessions, such as "M-x shell",
>>> then you should use the variable explicit-shell-file-name to point to
>>> that other shell (in your case, fish).
>> 
>> I understand that this is what Emacs expects. It seems to me that other
>> parts of a user’s system might go against this expectation, however. The
>> man page for login(1) says this, for example:
>> 
>>       Your user and group ID will be set according to their values in
>>       the /etc/passwd file. The value for $HOME, $SHELL, $PATH,
>>       $LOGNAME, and $MAIL are set according to the appropriate fields
>>       in the password entry. Ulimit, umask and nice values may also be
>>       set according to entries in the GECOS field.
>> 
>> That is to say, if a users runs chsh(1) and decides to use fish, then
>> SHELL is set to fish, it is inherited to all processes, and Emacs
>> breaks.
> 
> You could always add '(setenv "SHELL" "/bin/sh")' to your Emacs init file.
> 
> Best regards, Michael.