Hi, Thanks for your reply, but so far, I don't do any non-blocking read: as long as I can handle stdout and stderr together, I can do blocking reads.

I am afraid the other reply I got, from diotalevi, is correct: cleartool gets the user comments from an other device than stdin, and sends the prompt there as well.

I tried to eliminate the other options (e.g. that the prompt would have been there, but with a carriage return hiding it, or that it would have been buffered and non flushed).

I may have alternative strategies. Otherwise, I'll have to dig in the other APIs... OLE, and something called CAL.

Thanks anyway,
Marc