Hi Arnold, Thursday, November 09, 2000, 11:14:53 AM, you wrote: AR> We need asynchronious I/O of RT fifos. The RT kernel task writes data to AR> RT fifo and if data are available for Linux user mode process, we want AR> to have a SIGIO. We open RT fifo device with O_ASYNC or do fcntl with AR> O_ASYNC. I had a look to the source of rtl_fifo.c and I think this AR> feature is not yet implemented. Is there a easy patch to change the code AR> for async I/O ? or better it's possible to implement it generally? i thought of that too, but the only way i could imagine a scenario like this for the moment is to use the select-call on regular time intervalls. this means that you have to implement some kind of eventloop which calls a non-blocking select on the desired fifo. another alternative would be to create a new task/thread in userspace which does the needed select calls and throws a signal or interrupt if data is present. i don't know exactly if this is possible via a simple fork in your main application, but you could have a look at ACE (the adaptive communication environment) which offers "active objects". those active objects are methods running in independent threads. ACE and TAO webpage: http://www.cs.wustl.edu/~schmidt/TAO.html CU Alexander mailto:[EMAIL PROTECTED] -- [rtl] --- To unsubscribe: echo "unsubscribe rtl" | mail [EMAIL PROTECTED] OR echo "unsubscribe rtl <Your_email>" | mail [EMAIL PROTECTED] --- For more information on Real-Time Linux see: http://www.rtlinux.org/rtlinux/
