bug#66020: (bug#64735 spin-off): regarding the default for read-process-output-max

[Eli Zaretskii]

> Date: Thu, 21 Sep 2023 21:42:01 +0300
> Cc: stefankangas@gmail.com, monnier@iro.umontreal.ca, 66020@debbugs.gnu.org
> From: Dmitry Gutov <dmitry@gutov.dev>
> 
> On 21/09/2023 21:39, Eli Zaretskii wrote:
> >> Date: Thu, 21 Sep 2023 20:40:35 +0300
> >> Cc:stefankangas@gmail.com,monnier@iro.umontreal.ca,66020@debbugs.gnu.org
> >> From: Dmitry Gutov<dmitry@gutov.dev>
> >>
> >> Can we get the "recorded" value back from the pipe somehow?
> > There's F_GETPIPE_SZ command to fcntl, so I think we can.
> 
> I'll rephrase: is this a good idea (doing a +1 syscall every time we 
> read a chunk, I'm not sure of its performance anyway), or should we add 
> a new field to Lisp_Process after all?

If you indeed need the size, then do add it to the process object.