For example, to compress all HTML files on the fly, do this:

<Files *.html>
    SetHandler perl-script
    PerlHandler Apache::OutputChain Apache::GzipChain Apache::PassFile
</Files>

Browsers are supposed to declare that they can handle compressed input by setting the Accept-Encoding header. Unfortunately, many browsers cannot handle it, even if they claim that they can. Apache::GzipChain keeps a list of user agents, and also looks at the User-Agent header to check for browsers known to accept compressed output.

As an example, if you want to return compressed files that will in addition pass through the Embperl module, you would write:

<Location /test>
    SetHandler perl-script
    PerlHandler Apache::OutputChain Apache::GzipChain \
                Apache::EmbperlChain Apache::PassFile
</Location>

Watch the access_log file to see how many bytes were actually sent, and compare that with the bytes sent using a regular configuration.

Notice that the rightmost PerlHandler must be a content producer. Here we are using Apache::PassFile, but you can use any module that creates output.