diff options
| -rw-r--r-- | man2/timerfd_create.2 | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/man2/timerfd_create.2 b/man2/timerfd_create.2 index 698b160c98..dcfb63a81c 100644 --- a/man2/timerfd_create.2 +++ b/man2/timerfd_create.2 @@ -209,6 +209,23 @@ as an absolute value on the timer's clock. The timer will expire when the value of the timer's clock reaches the value specified in .IR new_value.it_value . +.TP +.BR TFD_TIMER_CANCEL_ON_SET +If this flag is specified along with +.B TFD_TIMER_ABSTIME +and the clock for this timer is +.BR CLOCK_REALTIME +or +.BR CLOCK_REALTIME_ALARM , +then mark this timer as cancelable if the real-time clock +undergoes a discontinuous change +.RB ( settimeofday (2), +.BR clock_settime (2), +or similar). +When such changes occur, a current or future +.BR read (2) +from the file descriptor will fail with the error +.BR ECANCELED . .PP If the .I old_value @@ -283,6 +300,24 @@ A will fail with the error .B EINVAL if the size of the supplied buffer is less than 8 bytes. + +If the associated clock is either +.BR CLOCK_REALTIME +or +.BR CLOCK_REALTIME_ALARM , +the timer is absolute +.RB ( TFD_TIMER_ABSTIME ), +and the flag +.BR TFD_TIMER_CANCEL_ON_SET +was specified when calling +.BR timerfd_settime (), +then +.BR read (2) +will fail with the error +.BR ECANCELED +if the real-time clock undergoes a discontinuous change. +(This allows the reading application to discover +such discontinuous changes to the clock.) .TP .BR poll "(2), " select "(2) (and similar)" The file descriptor is readable |