From: cgf AT cygnus DOT com (Christopher Faylor)
Subject: Re: tty hangs
21 Aug 1998 07:56:26 -0700
Message-ID: <19980821105448.A16913.cygnus.cygwin32.developers@cygnus.com>
References: <01BDCD14 DOT B3ECC300 AT sos>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
To: Sergey Okhapkin <sos AT prospect DOT com DOT ru>,
        "'cygwin32-developers AT cygnus DOT com'" <cygwin32-developers AT cygnus DOT com>

On Fri, Aug 21, 1998 at 03:02:22PM +0400, Sergey Okhapkin wrote:
>Tue Jul 21 09:32:23 1998  Christopher Faylor <cgf AT cygnus DOT com>
>
>	* pinfo.cc (pinfo_init): 0 is a very bad value for a default pgid.
>
>Chris, why did you make that change? Now command like "cat filename | less" 
>hangs when started from OS prompt and tty support is enabled. The hang is 
>because of lines in fhandler_tty_slave::read():

Basically because it is very much non-UNIX to have a pgid of 0.
I'm working on getting expect working and it does things with pgids
but it makes assumptions based on whether a process group's gid is != 0.
In some situations it never was != 0 so things became confused.

I haven't noticed the behavior you're reporting but I'll take a look
at it and fix it if I can.

cgf