Possible race in SYSV IPC (semaphores)

Corinna Vinschen corinna-cygwin@cygwin.com
Tue Nov 27 07:13:00 GMT 2012

On Nov 26 18:09, Lavrentiev, Anton (NIH/NLM/NCBI) [C] wrote:
> > I just checked in the change.
> Thank you.  I will test it as soon as it's available in a snapshot.
> > ...especially since I can't reproduce this.  I tried with cygserver
> > before and after my patch and in both cases your semaphore testcase
> > worked as expected with -d -l 7.
> I see.  Maybe this will help.  My sequence of actions:
> In an elevated cmd.exe, from Cygwin's /bin:
> cygrunsrv.exe -I cygserver -x /usr/sbin/cygserver.exe -a "-d -l 7"
> cygrunsrv.exe -S cygserver
> In a regular cmd.exe:
> a.exe
> (this is my testcase that locks/unlocks the semaphores).
> It never gets past iteration 1000.

Nope, no luck.  WJFFM.

You don't have space (or quota) issues on your hard disk by any chance?
The stderr output will go to /var/log/cygserver.log.  The file has a
size of about 60 Megs after 20K iterations and every run of the cygserver
service will append to the file.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

More information about the Cygwin mailing list