Tests: perl module.

test/perl/input_copy/psgi.pl

@@ -0,0 +1,10 @@
+my $app = sub {
+    my ($environ) = @_;
+
+    open(my $fh, ">&", $environ->{'psgi.input'});
+
+    my $len = int($environ->{'CONTENT_LENGTH'});
+    $fh->read(my $body, $len);
+
+    return ['200', ['Content-Length' => $len], [$body]];
+};