Defined in packages/acs-core/security-procs.tclChecks to see if a user is logged in. If not, redirects to
/register/index to require the user to register. When registration
is complete, the user will return to the current location. All
variables in ns_getform (both posts and gets) will be maintained.
Note that this will return out of its caller so that the caller need
not explicitly call "return". Returns the user id if login was
succesful.