Ah, but (and I should maybe have mentioned this before) the process runs for a long time, i.e. a couple of days.

It's a long batch-processing job. (That's why I'm using Pdlpp to code part of it, because I need to get up to C speed otherwise it takes forever).

So,
- need to get output during the program run, as the point of the output is to show progress.
- when I've been testing it to see if anything was showing up in the output file, I've been waiting a while and when nothing appeared I've been killing the process.

Best wishes, andye