nap() -- System Call (libc)

Sleep briefly
long nap(interval)
long interval;

nap() sleeps  for interval  milliseconds, or  until its process  receives a
signal, whichever occurs first.

If  it receives  no signal,  nap()  returns the  number of  milliseconds it
slept.  If it received a signal, it returns -1 and sets errno to EINTR.

See Also

libc,
sleep()

Notes

nap() is governed by the  granularity of the system clock.  Under COHERENT,
the system  clock ticks every ten milliseconds; thus,  the call nap(1); and
the call  nap(9); have the same  effect.  Note that nap()  is guaranteed to
sleep for  at least interval  milliseconds; thus, the  call nap(11); sleeps
for two clock ticks, or 20 milliseconds.

© 2012 by Stephen A. Ness