Re: weird less(1) CTRL-Z behaviour

[Robert Elz <kre%munnari.OZ.AU@localhost>]

    Date:        Wed, 12 Oct 2022 12:13:05 +0200
    From:        Thomas Klausner <wiz%NetBSD.org@localhost>
    Message-ID:  <Y0aTMSa8nDP2kA2E%yt.nih.at@localhost>

  | dir() { ls -al "$@" | less; }
  |
  | On -current (9.99.100 kernel from Oct 9, Userland from Sep 21, zsh
  | from May), when I CTRL-Z the less(1) and then want to go back in, it
  | doesn't work and I see the following:

As Chavdar said, this seems to be specific to zsh (the sh problem
is different, an in an area I have been working on in the past few
days, so just ignore that one for this purpose).

I tested a bunch of shells, zsh is the only one I saw fail this way.

The issue will be related to process group control, zsh must be
doing something different to other shells, and some recent
kernel change might have altered how that works - perhaps just
the timing.

That might be serpgrp() or TIOCSPGRP (or whatever equiv is being
used to change tge terminal's pgrp).

Perhaps this enough for someone to recognise a change they might
have made which could cause this.

kre