Date: Wed, 30 May 2001 12:54:10 +0000 (GMT) From: diman <diman@asd-g.com> To: Jiangyi Liu <gzjyliu@public.guangzhou.gd.cn> Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: Weird PT_DETACH Message-ID: <Pine.BSF.4.21.0105301250460.202-100000@portal.none.ua> In-Reply-To: <878zjf0zvr.fsf@fatcow.home>
next in thread | previous in thread | raw e-mail | index | archive | help
To attach debugger to a process please use PT_ATTACH
request instead of PT_DETACH. Use PT_DETACH to stop
debugging a process and leave it alone.
On 30 May 2001, Jiangyi Liu wrote:
> Hi all,
>
> The ptrace(2) man page is probably outdated. I used PT_DETACH in the
> following code, but it didn't run ./test. I also tried to use
> ptrace(PT_DETACH, pid, (caddr_t)1, 0) to detach, but it failed too.
>
> BTW, if I omit wait(0) and ptrace(PT_DETACH, ...) in the code, after
> it runs there is a process sticking to the system. Even kill -9 can't
> kill it.
>
> $ ps aux | grep jyliu
> ...
> jyliu 423 0.0 0.1 216 100 p2 TX 7:41AM 0:00.00 (test)
> ...
> $ kill -9 423
> $ ps aux | grep jyliu
> ...
> jyliu 423 0.0 0.1 216 100 p2 TX 7:41AM 0:00.00 (test)
> ...
>
> So it's still there. Quite funny. Any clue?
>
> Jiangyi
>
> ---code begins here
> #include <unistd.h>
> #include <sys/types.h>
> #include <sys/ptrace.h>
>
> int main()
> {
> pid_t pid;
>
> if(!(pid=fork())) {
> /* child */
> ptrace(PT_TRACE_ME, 0, 0, 0);
> puts("child speaking");
> execve("./test", NULL, NULL);
> } else {
> wait(0);
> ptrace(PT_DETACH, pid, 0, 0);
> exit(0);
> }
> }
> ---code ends here
>
> To Unsubscribe: send mail to majordomo@FreeBSD.org
> with "unsubscribe freebsd-hackers" in the body of the message
>
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.21.0105301250460.202-100000>