Davide Libenzi wrote: > On Thu, 27 Sep 2007, Michael Kerrisk wrote: > >> Davide, >> >> A further question: what is the expected behavior in the >> following scenario: >> >> 1. Create a timerfd and arm it. >> 2. Wait until M timer expirations have occurred >> 3. Modify the settings of the timer >> 4. Wait for N further timer expirations have occurred >> 5. read() from the timerfd >> >> Does the buffer returned by the read() contain the value >> N or (M+N)? In other words, should modifying the timer >> settings reset the expiration count to zero? > > Every timerfd_settime() zeroes the tick counter. So in your scenario it'll > return N.
Thanks Davide. I modified the first para of the read description to make this clear: read(2) If the timer has already expired one or more times since its settings were last modified using timerfd_settime(), or since the last successful read(2), then the buffer given to read(2) returns an unsigned 8-byte integer (uint64_t) containing the number of expirations that have occurred. (In the earlier version of the page the text talked about expirations "since the timer was created".) Cheers, Michael -- Michael Kerrisk maintainer of Linux man pages Sections 2, 3, 4, 5, and 7 Want to help with man page maintenance? Grab the latest tarball at http://www.kernel.org/pub/linux/docs/manpages/ read the HOWTOHELP file and grep the source files for 'FIXME'. - 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/