I've changed your code to read: 
if (fork()==0) {
   print "child1\n";
   system ("ls -al $ARGV[0]");
   exit;
}
if (fork()==0) {
   print "child2\n";
   system ("df -k $ARGV[1]");
   exit;
}
wait;
wait;
print "Done!\n";

[download]
and it works fine. So your problem might be one or both of:
  1. The programs you call don't work as you think they should.
  2. You can't seperate the ouput by looking at it. The lines of output usually are mixed.

In reply to Re: How to use multiple processors with fork in unix? by Skeeve
in thread How to use multiple processors with fork in unix? by Anonymous Monk

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