This is the mail archive of the mailing list for the Cygwin project.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: Please try the latest snapshot -- it is close to cygwin 1.5.6

On Fri, Dec 26, 2003 at 09:13:36PM -0500, Pierre A. Humblet wrote:
>At 05:59 PM 12/26/2003 -0500, Christopher Faylor wrote:
>>I added strace debugging.  You can use that as a clue for what I was
>>talking about and make it visible if you can't run exim under strace.
>I put a try_to_debug(1). Waiting for something to happen.

Thanks, for debugging this but that wasn't specifically what I was
talking about.  If you go back and read the message, you'll see that I
was talking about your 'get_proc_lock' problem.

>>>Also, while running sysinternals I noticed to the exim daemon still had tty
>>>related handles, despite setsid(). Ditto for inetd.
>>Calling setsid does not automatically eliminate tty handles.
>This is what inetd does:
>	if (setsid() == -1)
>		return (-1);
>	if (!noclose && (fd = open(PATH_DEVNULL, O_RDWR, 0)) != -1) {
>		(void)dup2(fd, STDIN_FILENO);
>		(void)dup2(fd, STDOUT_FILENO);
>		(void)dup2(fd, STDERR_FILENO);
>Before your last changes, strace was showing 
>  160  282749 [main] inetd 34569887 close: close (2)
>  361  283110 [main] inetd 34569887 fhandler_tty_slave::close: decremented open_fhs 0, archetype usecount 2
>  198  283308 [main] inetd 34569887 fhandler_tty_slave::close: just exiting because archetype usecount is > 0
>  163  283471 [main] inetd 34569887 close: 0 = close (2)
>  160  283631 [main] inetd 34569887 dtable::dup2: 2 = dup2 (3, 2)
>Now usecount is even higher
>  159  292878 [main] inetd 1086339 close: close (2)
>  181  293059 [main] inetd 1086339 fhandler_tty_slave::close: decremented open_fhs 0, archetype usecount 3
>  313  293372 [main] inetd 1086339 fhandler_tty_slave::close: just returning because archetype usecount is > 0
>  175  293547 [main] inetd 1086339 close: 0 = close (2)
>  158  293705 [main] inetd 1086339 dtable::dup2: 2 = dup2 (3, 2)
>I looked at your latest change in 
>It seems to me that setsid should simply call close all the time if (cygheap->ctty)
>and let close() take care of usecount.

I had already checked in a change to this effect but I missed...

>Ditto in pinfo::set_ctty where a problem similar to the one you
>addressed also exists.

this.  Thanks.  I've checked in a new fix as well as a similar change
for close_all_files.

>I don't think that will take care of everything, but I can't follow
>what's happening when tracing sh -c inetd

I tried the current CVS version and I don't see any stray tty garbage
with inetd.  I never tried this with an older snapshot, however, so I
don't know if I would have been lucky before.  I did try a much simpler
test case which worked incorrectly with CYGWIN=tty and correctly after
today's initial setsid change.


Unsubscribe info:
Problem reports:

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]