problems with blocking pipes, threading

[Sven Drescher]

> If you want to see whether this is really the problem, you might
> write a sample program like  sys.stdout.write('Hello\n');
time.sleep(1000.0)
> and verify that its pipe blocks this way.  Then add sys.stdout.flush()
> after the write, and see if anything is different.

Thanks for the hint! That's the problem. The programm works correct, if
using 'sys.stdout.write()'.
But in my further work I start processes, where I cannont know, how the
standard output is realized. Is there a possibility to flush the child's
stdout??? Or is there a complete other way to catch the child's stdout in
'real-time'???

Thanks!
Sven