Am 20.11.2013 um 07:58 schrieb Gilles Chanteperdrix <[email protected]>:
> On 11/20/2013 03:33 PM, Michael Haberler wrote: >> I'm looking for a simple method to post an event from an RT thread so >> a userland non-RT thread can wait for, and pick it up via a file >> descriptor (without switching the originating thread to primary >> domain, of course) >> >> event context can be minimal since the userland handler can figure; >> actual data transfer not required - event number or mask a plus >> >> purpose would be integration into existing event loops; only >> RT->userland signalling needed >> >> if it's possible from a kernel RT context, it's a plus >> >> --- >> >> one scheme I thought of was: using rt_event services, monitor the >> event flag in a userland shadow thread and post to an eventfd whose >> other side could be integrated into an event loop. Making sense? >> >> thanks in advance, >> >> Michael >> >> ps: this needs to be portable across RT kernel variants; my approach >> for RTAI would be to use rt_request_srq() and post to an eventfd from >> the Linux context > > You may use XDDP IPC for that, see: > http://www.xenomai.org/documentation/xenomai-2.6/html/api/xddp-echo_8c-example.html in the RT thread, I'd need to do a non-blocking read of the XDDP socket or test in some way if a message is present (man 2 recvfrom indicates by default it blocks until data available) what would be the right/fastest way to do this - do the recvfrom() with the MSG_DONTWAIT option? - Michael _______________________________________________ Xenomai mailing list [email protected] http://www.xenomai.org/mailman/listinfo/xenomai
