rc.firewall script confusion

[doughyi8u]

It's been years since I even tried to write shell scripts and forgot some things. What I'm missing is in the stock rc.firewall it says at the beginning:

#suck in the configuration variables
if [ -z "${source_rc_confs_defined}" ]; then
    more code here
fi

where does ${source_rc_confs_defined} come from? The top line says #!/bin/sh -. I'm not sure but doesn't the "-" imply that this is run as a login shell?

 

[phoenix]

rc.firewall is called by the RC system, which gets all of its configuration info via /etc/defaults/rc.conf, /etc/rc.conf, and /etc/rc.conf.local, in that order. /etc/rc is the initial file, and then it pulls in scripts under /etc/rc.d/ as needed.