in reply to Re^3: mod_perl input filter error
in thread mod_perl input filter error

I'm saying you have another typo

But yes, I'm saying this without trying to run apache... the most runnable sample code comes from the test suite :) for example https://metacpan.org/source/SHAY/mod_perl-2.0.9/t/filter/TestFilter/in_bbs_consume.pm