bug#21777: 25.0.50; gud-gdb uses a pager, which is harmful inside emacs

[Dima Kogan]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Dima Kogan <dima@secretsauce.net>
>>
>> Hi. Thanks for replying. Looking at gdb/utils.c, apparently gdb looks at
>> the EMACS environment variable, which was set previously but is not
>> anymore:
>> 
>> 2. patch gdb to look at INSIDE_EMACS not EMACS
>
> That should be done regardless, I will submit a patch to GDB.

Thanks for doing that!


>> 3. handle this inside emacs, not relying on gdb behavior
>> 
>> I like 3. Emacs should be responsible for things emacs wants, not
>> external applications, even if they're GNU applications.
>
> 3 is okay in principle, but you didn't show any specific suggestions.
> What did you have in mind?

gud-gdb.el can send a "set height unlimited" command when it starts the
gdb process. I'm happy to give you a patch, if you want.


> Please also keep in mind that "M-x gud-gdb" is a legacy command, and
> the more modern "M-x gdb" doesn't have that problem.

I didn't like it when I tried it the last time; don't remember what
specifically was the problem. But if we're still shipping gud-gdb, it
should work properly, I think.


> There's also:
>
>  4. Fix this locally in your GDB init files (using GDB scripting
>     facilities).

But then it'll annoy others.


>> Also, it looks like gdb checks EMACS in a few more places, and I haven't
>> looked at those yet.
>
> Maybe I'm missing something, but I don't see any additional places
> except the one pointed out by Andreas.

You're right. I was looking at the readline in their tree, but that's
unrelated.