Added os.sync call to ensure all files are written before ARBD/NAMD run

arbdmodel.py

@@ -705,6 +705,7 @@ class ArbdModel(PdbModel):
         self.writePdb( outputPrefix + ".pdb" )
         self.writePsf( outputPrefix + ".psf" )
         self.writeArbdFiles( outputPrefix, numSteps=numSteps, outputPeriod=outputPeriod )
+        os.sync()
 
         ## http://stackoverflow.com/questions/18421757/live-output-from-subprocess-command
         cmd = (arbd, '-g', "%d" % gpu, "%s.bd" % outputPrefix, "%s/%s" % (outputDirectory, outputPrefix))
@@ -967,3 +968,4 @@ component "data" value 3
         if outputDirectory == '': outputDirectory='.'
         self.writePdb( outputPrefix + ".pdb" )
         self.writePsf( outputPrefix + ".psf" )
+        os.sync()