This is the bsdmainutils package from Debian. It's a collection of
common BSD utilities, compiled from different sources, by the Debian
folks. It includes tools such as the classic 'calendar'.

This SlackBuild uses the Debian sources to create a suitable
package for Slackware. Hdate (and its python bindings) is a
build-time dependency, that is built in this same package, but not
installed. Because it's a package for Slackware, and not Debian, it
bears the following differences from the original Debian package:

- Utilities that conflict with Slackware's util-linux have been
  removed.
- /etc/cron.daily/bsdmainutils and /etc/default/bsdmainutils have
  been installed in /usr/doc as cron.daily, and bsdmainutils.default,
  respectively. Please verify that these scripts work on your machine
  before using them in production. They were tailored for Debian, not
  Slackware!
- The postinst and prerm scripts aren't installed, because they're
  unnecessary in the context of Slackware.
- Slight structure alterations to fit with the Slackware filesystem.
  See the SlackBuild for more details.