On Sun, 11 Mar 2007, Davide Libenzi wrote: > This patch introduces a new system call for timers events delivered > though file descriptors. This allows timer event to be used with > standard POSIX poll(2), select(2) and read(2). As a consequence of > supporting the Linux f_op->poll subsystem, they can be used with > epoll(2) too. > The system call is defined as: > > int timerfd(int ufd, int clockid, int tmrtype, const struct timespec *utmr); > > The "ufd" parameter allows for re-use (re-programming) of an existing > timerfd w/out going through the close/open cycle (same as signalfd). > If "ufd" is -1, s new file descriptor will be created, otherwise the > existing "ufd" will be re-programmed. > The "clockid" parameter is either CLOCK_MONOTONIC or CLOCK_REALTIME. > The "tmrtype" parameter allows to specify the timer type. The following > values are supported: > > TFD_TIMER_REL > The time specified in the "utmr" parameter is a relative time > from NOW. > > TFD_TIMER_ABS > The timer specified in the "utmr" parameter is an absolute time. > > TFD_TIMER_SEQ > The time specified in the "utmr" parameter is an interval at > which a continuous clock rate will be generated. >
Duh! Forgot to update the documenation. Now timerfd() gets an itimerspec. For TFD_TIMER_REL only the it_interval is valid, and it's the relative time. For TFD_TIMER_ABS, only the it_value is valid, and that the expiry absolute time. For TFD_TIMER_SEQ, it_value tells when the first tick should be generated, and it_interval tells the period of the following ticks. - Davide - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
