Re: epicsThreadSleep and epicsThreadSleepQuantum

["Konrad, Martin via Core-talk" <core-talk@aps.anl.gov>]

Hi Mark,
>> If we want to sleep for a minimum amount of time we might want to
>> call nanosleep(0) instead.
Sorry, I actually meant to say "epicsThreadSleep(0)" here.

> But that will not work on Windows or vxWorks.
On Windows epicsThreadSleep is implemented using Sleep(). Sleep(0)
behaves similar to nanosleep(0):

"A value of zero causes the thread to relinquish the remainder of its
time slice to any other thread that is ready to run." [1]

For vxWorks' taskDelay(0) I'm not 100% sure - the documentation I found
[2] doesn't say explicitly. But the fact that epicsThreadSleep() clamps
negative arguments to 0 [3] suggests that taskDelay(0) does what you
would expect it to do...

-Martin

[1]
https://docs.microsoft.com/en-us/windows/desktop/api/synchapi/nf-synchapi-sleep
[2]
https://www.ee.ryerson.ca/~courses/ee8205/Data-Sheets/Tornado-VxWorks/vxworks/ref/taskLib.html#taskDelay
[3]
https://github.com/epics-base/epics-base/blob/3.15/src/libCom/osi/os/vxWorks/osdThread.c#L311

-- 
Martin Konrad
Facility for Rare Isotope Beams
Michigan State University
640 South Shaw Lane
East Lansing, MI 48824-1321, USA
Tel. 517-908-7253
Email: konrad@frib.msu.edu