Monks, I have been stuck on this problem for the good majority of a week now and cannot explain it. I have developed a client/server application useful for CGI scripts that I personally wanted to run with root privileges but not directly. This has allowed me to run a server as root and install my own security checking rather than rely on something like suexec or suidperl. Anyway my trouble begins with a function that I created that listens for a "termination" message from the client before logging the conversation as a success (this also listens for "resend" messages much like TCP error-control). The function follows: 
sub FinishUp {
 my ($clientid) = @_; my $incoming="";
 while ( (sysread $clientid, $incoming, 1024) && != 0 ) { 
  print "Received Response from $clientid: $incoming\n";
  if ($incoming =~ /Resend/) { return "yes", "yes"; }   
  if ($incoming =~ /Finished|OK/) { return "no", "no"; }
 }
}

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The strange and unexplainable part is...this works perfect for the majority of functions I call it from, however, there are 3 of the approximately 20 functions where the finishup function exits with this error message: Use of uninitialized value in integer ne (!=) at common.pl line 250. I fail to understand this because the finishup function is called the exact same way with the exact same parameters (the client ID) everytime. use strict and perl -w are outputting just that error message - everything else runs perfect. If anyone might be able to shed a little light on this I would greatly appreciate it. -Adam Stanley Nethosters, Inc.

In reply to Unexplainable Client/Server trouble by astanley

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