Does AIX have a function like sginap()?

[John D. McCalpin]

I am working on a FORTRAN application that needs to sit and wait for
certain data files to be completely written.  The basic loop is

	OPEN(in_unit,....)
 8888	READ(in_unit,ERR=8888,END=8888) data
	CLOSE(in_unit)

This works fine, but uses up lots of system time that would be better
spent by the other process that is supposed to be writing the data!

On the Silicon Graphics machines, there is a nice function called
'sginap(i)' which:
	-- with an argument of 0, will release control to any other
		process with the same or higher priority; or
	-- with an argument i>0, will sleep for 'i' clock ticks.

The modified code segment:
	OPEN(in_unit,....)
 8888	idummy = sginap(0)
	READ(in_unit,ERR=8888,END=8888) data
	CLOSE(in_unit)
runs much more efficiently.

I cannot use the normal 'sleep()' routines, since the actual latencies
involved are much smaller than 1 second, and the OPEN/READ/CLOSE
sequence needs to be done several times per second.

Is this functionality available in a more standard UNIX call?  

Does AIX have this functionality?  This is important, since I really
want to run the application on a network of IBM 320's sharing files
via NFS.
--
John D. McCalpin			mccalpin at perelandra.cms.udel.edu
Assistant Professor			mccalpin at brahms.udel.edu
College of Marine Studies, U. Del.	J.MCCALPIN/OMNET