Dear List, I'm writing an RTC device driver in linux 2.4.7. kernel on PPC platform. It uses an RTC chip dependent kernel exported function. In this function I have to determine when the second changing as accurately as I can. I read the seconds register in a while loop. It can takes up to 1 sec, which is a very long time. How should I use the schedule() to let other processes to do some other job and make the smallest possible mistake detecting the second changing? TIA && Good byte! -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/