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From: Eric Blake <ebb9@byu.net>
Subject:  Re: job control "Bad address" error
Date: Tue, 16 Jun 2009 15:28:14 +0000 (UTC)
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Haojun Bao <baohaojun <at> gmail.com> writes:

> type the command:
>     cat|cat <Enter>
> 
> type ^Z, type
>     bg <Enter>

I can also reproduce it under cygwin 1.7, and further clarified that it is the 
second cat that is failing:

$ sleep 100 | cat
^Z
$ bg
cat: -: Bad address

I'm not quite sure how to strace this, since you can't use ^Z to suspend an 
active strace.  But my guess is that there is a bug in cygwin1.dll pipe 
handling code, such that it dereferences bad memory when resuming execution of 
a read from a pipe after a SIGSTOP; cat is just reporting the EFAULT from a 
failed read() call.

-- 
Eric Blake
volunteer cygwin coreutils maintainer



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