From: Stefan Sperling <stsp@stsp.name>
Subject: Re: Bug: tog suspend/continue
To: Christian Weisgerber <naddy@mips.inka.de>
Cc: gameoftrees@openbsd.org
Date: Tue, 14 Jan 2020 15:30:25 +0100

On Mon, Jan 13, 2020 at 09:56:16PM -0000, Christian Weisgerber wrote:
> I hit a bug in tog:
> 
> If you start a view that performs work in a background thread (log,
> blame), suspend tog with ^Z and then continue it, the display will
> be garbage.  For tog log, ^L will recover.  Strangely, any further
> ^Z will be ignored.
> 
> A simple way to reproduce with the OpenBSD src git:
> 
> $ tog log -r src.git usr.bin/ssh
> ^Z
> $ fg
> 
> If the background thread has already finished, suspend/continue
> works fine.

I bet this is related to how signals get delivered to threads.
Does anyone here have some expertise in this area?