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Date: Thu, 30 Nov 2006 08:31:15 -0800
From: Brian Dessent <brian AT dessent DOT net>
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To: Simon Marlow <simonmar AT microsoft DOT com>
CC: "cygwin AT cygwin DOT com" <cygwin AT cygwin DOT com>
Subject: Re: Ctrl-C and non-cygwin programs
References: <A50988F69402FB47B4D860B67FB51FA13462F87C AT EA-EXMSG-C311 DOT europe DOT corp DOT microsoft DOT com>
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Simon Marlow wrote:

> Then run the program, hit Ctrl-C and see what happens.  The behaviour differs depending on the environment:
> 
>   * In a Cygwin shell started from cygwin.bat, with the CYGWIN
>     environment variable empty: correct behaviour, Ctrl-C is caught
>     and handled.
> 
>   * In a Cgwin shell started from cygwin.bat, with CYGWIN=tty:
>     Ctrl-C apparently just kills the child process, the event is
>     not caught.
> 
>   * In an xterm (Cygwin), with Cygwin bash: again, the child process
>     is just killed.
> 
>   * In a CMD.EXE shell, Ctrl-C is caught and handled.

The problem is that in the case of CYGWIN=tty or under xterm/rxvt, the
program is not attached to a Windows console at all.  It is running
under a Cygwin pseudoterminal (pty), which to a non-Cygwin app will look
as if it was totally detached with just pipes connected to stdin and
stdout.  Since there's no console, there's no way for a
ConsoleCtrlHandler event to fire.

Brian

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