GNU Finger
5.3 Site Specific Functions
If you are interested in customizing GNU Finger's output, then the
`lib/site' directory is the right place to start. If you would
like to add new code for displaying faces, or have a particularly
interesting "long" information output format, I would be glad to
include it as unsupported code in the next release of GNU Finger. (I
will direct correspondence regarding your code to you.) You can find
other contributed code in `lib/site', most notably different user
info formats and code to handle different bit map file formats. The only
file supported in `lib/site' is `userinfo.c'.