Re: Program Execution: output does not appear

[Tony Godshall <togo@of.net>]

According to Tony Godshall,
> According to Angelo R. Rossi,
> > Hello:
> > 
> > I am using a large molecular dynamics program in the following manner:
> > 
> >                               charmm <input.file  >output.file
> > 
> > The problem is that the file output.file is created, but remains empty.
> >  After a while, the file fills with some output but still holds back
> > much of it.
> > 
> > What is happening here?  This is the first time anything like this has
> > happened.  Usually, output appears immediately.  It seems as if it is
> > going into a buffer and not being put to the hard drive.
> > Please help with this.
> > 
> > I am using debian unstable and uname -a gives:
> > 
> > Linux thebox 2.6.11 #2 SMP Thu May 26 20:53:11 CEST 2005 i686 GNU/Linux
> > 
> > Please help if you can.
> 
> Does doing "sync;sync;sync" help?
> 
> Does the file size show growth?

I think the app needs to to call Unix function fflush(NULL) 
to flush its buffers to disk.  I don't know charmm but I
assume it's open source and you can insert such a call.

  man 3 fflush