foreach $host (@hosts) {
   pipe($fhr{$host}, $fhw{$host});
   if (fork() == 0) { # child process spawned
      #do stuff and then write to pipe like this:
      close $fhr{$host};
      print { $fhw{$host} } "$mystr";
      close $fhw{$host};
   }
}

while (wait() != -1) { #wait for children to finish }


foreach $host (@hosts) {
    close $fhw{$host};
    chomp ($mystring=<$fhr{$host}>);
    close $fhr{$host};
    print "DATA from $host: $mystring";
}