s6-rc is a service manager for s6-based systems, i.e. a suite of
programs that can start and stop services, both long-running daemons and
one-time initialization scripts, in the proper order according to a
dependency tree. It ensures that long-running daemons are supervised by
the s6 infrastructure, and that one-time scripts are also run in a
controlled environment.

NOTE:
s6-rc has a "live directory" where it puts some internal files that are
needed at runtime, which defaults to /run/s6-rc. This can be changed to
another directory by passing LIVE_DIR=/path/to/directory environment
variable to this SlackBuild script like below:

    LIVE_DIR=/path/to/directory ./s6-rc.SlackBuild

Make sure /path/to/directory is readable and writable by s6-rc, or it
will not work correctly. A good recommendation is to put the live
directory inside a RAM filesystem (e.g., tmpfs).