RE: PATCH: Run builtins, functions, etc. under zpty

["Andrej Borsenkow" <Andrej.Borsenkow@xxxxxxxxxxxxxx>]

Attempt to run any (external) command with zpty under Cygwin now results in:

zsh: can't set tty pgrp: not owner

(from child process) and hanging? zsh. That is what I have in process list:

$ ps -l
      PID    PPID    PGID     WINPID TTY  UID    STIME COMMAND
     1696       1    1696       1696   0 1006 15:22:33 /usr/bin/bash
      580       1     580        580   1 1006 15:22:34 /usr/bin/zsh
     2328     580    2328       2328  -1 1006 15:22:52 /usr/bin/zsh
     2188    1696    2188       1904   0 1006 15:28:35 /usr/bin/ps

for "zpty sh /bin/sh". Zsh does not appear to execute command at all, but it
does not exit either.

This happens with the version of cygwin that did work before, so it is very
much related to the changes in zsh. The messages above comes from attachtty,
but I am not sure when it is executed and what happens after this, i.e. why
zsh apparently "hangs".

-andrej