How to clean out Zombies?

[jian at kuhub.cc.ukans.edu]

Help Wanted:

   I am writting a program that works like a daemon process. The master
will run forever on UNIX and listen a port for request calls. In order to 
make the master process be able to handle multiple calls at the same time, 
I design the program to spawn out child process to perform work whenever a 
request call comes. The child process will terminate itself when a clear 
call signal is received. Here is the problem. When I use "ps ux" shell 
command to check the status of processes on the system, I found lots of 
Zombie processes. If I terminate the master process, all of zombies are gone.
However, I want the master process run forever. What should I do inside the 
program in order to make child processes really terminate themself without 
leave any zombies on the system. I would appreciate any helps.

Thanks in advance.
   
Jian Q. Li
jian at kuhub.cc.ukans.edu