If your $_ comparison doesn't work, that usually indicates that it doesn't hold what you expect.

print $client "Thank you for your command: ->$_<-\n";
print OUT "->$_<-\n";
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In my testing, I saw some spurious \r (carriage return) characters -- that may have been due to my use of a telnet client. A simple tr/\r//d; before the chomp fixed it for me.