dup_proc_pipe

Christopher Faylor me@cgf.cx
Fri Jan 7 14:08:00 GMT 2005


On Thu, Jan 06, 2005 at 10:47:04PM -0500, Pierre A. Humblet wrote:
>         * pinfo.cc (_pinfo::dup_proc_pipe): Can't close proc pipe when
>execing
>         or we will suffer an exit code race.
> 
>Even when you will wait for yourself, as a top Cygwin process?

Yes this is an issue for an exec from the command line of a windows
process.  I'll fix this.

>In the same vein, if the last process in a chain is a Windows
>process, :exit gets called by the Cygwin parent with norecord, so the
>state is not set to PID_EXITED and the logical parent is not alerted.
>It's not critical, but it would be easy to make use of the return
>value of ciresrv.sync, which could be placed in the P_OVERLAY case.

It doesn't look like PID_EXITED gets used for anything really critical
so this isn't a big deal, but you should be able to set this whenever
process exit is detected.  I tried the obvious solution of just setting
it in child_info::sync but that is racy.  I'm too tired tonight to come
up with a better scenario.

>Also, PID_EXITED is used in the case
>(!created && createit && (procinfo->process_state & PID_EXITED)
>but it's not a sure way of handling the transient because the new
>process may not have access rights to the old pinfo, leading to a
>hard failure. To minimize the likelihood of such an event, one could
>call myself->release () before ExitProcess. 
>The order is already optimized in remove_proc.

Ok.  I'll add this.

cgf



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