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From: Greg <gkurz@fr.ibm.com>
To: linux-kernel@vger.kernel.org
Subject: sigsuspend() and ptrace()
Date: Fri, 04 Nov 2005 09:57:49 +0100	[thread overview]
Message-ID: <436B228D.2000309@fr.ibm.com> (raw)

Hi,

My program uses gdb to attach to a process and make it execute a specific
function thanks to the gdb 'call' command. This works quite well unless the
attached process is sleeping in sigsuspend(). I peeked into the kernel sources
and saw that the typical sigsuspend() implementation is like this :

while (1) {
	schedule();
	if (do_signal())
		return -EINTR;
}

When using ptrace attach, the target process receives a SIGSTOP but there
isn't *of course* any handler to SIGSTOP. And no way for the process to return
to userland... is it implemented that way on purpose ? How can I make suspending
processes do some *alternative* work with gdb ?

Thanks.

Greg.


             reply	other threads:[~2005-11-04  8:57 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-11-04  8:57 Greg [this message]
2005-11-19  4:22 ` sigsuspend() and ptrace() Daniel Jacobowitz
2005-11-23 20:23   ` Greg

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