bug#33050: 27.0.50; [macOS] Problem with process input with process-connection-type nil

[Eli Zaretskii]

> Date: Sat, 27 Oct 2018 22:28:15 +0200
> From: charles@aurox.ch (Charles A. Roelli)
> CC: eliz@gnu.org, 33050@debbugs.gnu.org, fgunbin@fastmail.fm,
>       alan@idiocy.org
> 
> >                                       However, _for subprocesses used
> >    by Lisp programs for internal purposes, it is often better to use a
> >    pipe_, because pipes are more efficient, and because they are immune
> >    to stray character injections that ptys introduce for large (around
> >    500 byte) messages.
> 
> Does anyone recall where these "character injections" come from?  ISTR
> that these no longer happen...  Maybe this is a reference to the code
> deleted here:
> 
> https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=2b0a91e78f83fb446cc38efb99399e83ad2cded3
> (as seen, e.g., in Bug#32438)

Probably.

> Also, both "process-send-region" and "process-send-string" (in master)
> claim to split their process input if it is longer than 500
> /characters/ (not bytes) -- but reading through the code in process.c,
> it's not clear where (or if) this still happens.

pty_max_bytes was deleted as well, so I think you are right.