Segmentation fault(LINUX) and no idea why!

[Thomas Thiele]

Hallo!

In my program I create a new thread. In this new thread I fork and
replace the child with an other program
using excel. Normaly I have up to four threads with this procedure. So I
have a number of threads and the same numbers of childs (the called
program)

The problem is sometimes (relativly seldom, so it's unreproducible ;-( )
I get a segmantation fault and the pytthon interpreter stops.

But I if the segmentation fault happens, one of the childs is not
running anymore. (I don't know is that the reason or a  result)
A little testprogram with the same construction shows that if a
segmentaltion fault happens in one child, the parant keeps running.
I get no traceback from the interpreter.

My Question is, where can I look for the problem. Why does the
interpreter (-> the whole program) die.  What can be the reason?