.TH rtapi_delay "3rtapi" "2006-10-12" "LinuxCNC Documentation" "RTAPI" .SH NAME rtapi_delay \- Busy-loop for short delays .SH SYNTAX .HP void rtapi_delay(long int \fInsec\fR) .HP void rtapi_delay_max() .SH ARGUMENTS .IP \fInsec\fR The desired delay length in nanoseconds .SH DESCRIPTION \fBrtapi_delay\fR is a simple delay. It is intended only for short delays, since it simply loops, wasting CPU cycles. \fBrtapi_delay_max\fR returns the max delay permitted (usually approximately 1/4 of the clock period). Any call to \fBrtapi_delay\fR requesting a delay longer than the max will delay for the max time only. \fBrtapi_delay_max\fR should be called before using \fBrtapi_delay\fR to make sure the required delays can be achieved. The actual resolution of the delay may be as good as one nano-second, or as bad as a several microseconds. .SH REALTIME CONSIDERATIONS May be called from init/cleanup code, and from within realtime tasks. .SH RETURN VALUE \fBrtapi_delay_max\fB returns the maximum delay permitted. .SH SEE ALSO \fBrtapi_clock_set_period(3rtapi)\fR