There is no support for buffering IO for stdout. I can put in a feature request, but it will be for non-default behavior.

Our runtime buffers on line boundaries by default.

There is an obvious problem with making it default - users expect that write(*,*) statements for debug purposes come out in a timely manner. If you buffer them, you cannot rely on them for debug.

also, for our cluster customers: if stdout is buffered and the distributed app is killed, it is very common to kill remote processes and destroy their buffers, hence NO output would come out.

I will put in a feature request for a non-default way to enable buffering of stdout. I doubt we want to do this for stderr, as that information should definitely be delivered in near-real time.

ron

Feature Request ID DPD200236607

Ronald,

I found this on stackoverflow.com

fpost_t pos;
fgetpos(stdout, &pos);
return (pos >= 0);

As to if this alwasy works I cannot say.

Jim Dempsey

We are facing the same problem and would like to know the status of the feature request.

How about adopting the gfortran/g77 behavior where redirection to a file cause the I/O to be buffered?

Best
John