rc.d scripts and rc.conf variable defaults

[Ian Lepore]

We have about 165 scripts in etc/rc.d.  22 of them handle their own
default values for configuration variables using ${var:=default} or
${var:-default}.  Presumably all the others rely on defaults/rc.conf
providing the default values.

Is there a standard, written or not, covering this?

rc.conf(5) says that defaults/rc.conf is the thing that includes your
/etc/rc.conf, and that would certainly guarantee that the system-
provided defaults are in place, but the current implementation doesn't
actually work that way.  rc.subr is currently forgiving of a missing
defaults file.

I'd prefer that the system rc.d scripts relied on defaults/rc.conf
alone and individual rc.d scripts not be cluttered up with :- syntax.
 While rc.conf(5) strongly implies the file is required, it doesn't
exactly say so.  Should it?

-- Ian

[Warner Losh]

We have about 165 scripts in etc/rc.d. 22 of them handle their own
default values for configuration variables using ${var:=default} or
${var:-default}. Presumably all the others rely on defaults/rc.conf
providing the default values.
Is there a standard, written or not, covering this?

When /etc/defaults/rc.conf was created, the standard was everything belongs
there to protect the user from default churn.

rc.conf(5) says that defaults/rc.conf is the thing that includes your
/etc/rc.conf, and that would certainly guarantee that the system-
provided defaults are in place, but the current implementation doesn't
actually work that way. rc.subr is currently forgiving of a missing
defaults file.

Yes, it was implemented that way a long time ago, but there was a switch to
a list of rc files to read at some point and the docs weren't updated.

I'd prefer that the system rc.d scripts relied on defaults/rc.conf
alone and individual rc.d scripts not be cluttered up with :- syntax.
While rc.conf(5) strongly implies the file is required, it doesn't
exactly say so. Should it?

IMHO, yes. It's certainly was the intent when this stuff was invented.

Warner