Hello, I am trying to learn about the fork process .
I found this snippet of code so I may learn more about the
process but I do not understand it . Can anyone explain how the below snippet works?

@STATE = split //, ".URRUUxR";
         @data = split//,"\nrekcah xinU / lreP rehtona tsuJ";
         
         sub make_pipe_and_fork {
           @pipestate{"r$fhno", "u$fhno"}=(P,P);
           pipe "r$fhno", "u$fhno";
           ++$fhno;
           ($pid *= 2) += $is_child = !fork();
           map {
            $STATE=$STATE[$is_child ^ ord($pipestate{$_}) & 6];
            $pipestate{$_} = (/^$STATE/i ? $STATE : close $_);
          } keys %pipestate
        }
        make_pipe_and_fork;
        make_pipe_and_fork;
        make_pipe_and_fork;
        make_pipe_and_fork;
        make_pipe_and_fork;
        
        map {
          $pipestate{$_} =~ /^[P.]/ && close $_
        } %pipestate;
        
        wait until $?;
        
        map { /^r/ ? <$_> : 1 } %pipestate; 
        
        $_ = $data[$pid];
        sleep rand(2) if /\S/;
        print
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