Here is a super-simple piped input, using a perl script.

#the Main script to run

#!/usr/bin/perl -w
$|++;
open( H, " | other_script") or die "$!\n";
print H "hi\n";
sleep 1; #let other script print before dieing  
__END__
#####################################
#the other_script

#!/usr/bin/perl
$|++;
my $in = <>;
print "$in\n"
__END__
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