> In our login UDC we limit the number of sessions a user can
> take with the IF
>   JOBCNT("@S:!HPUSER.!HPACCOUNT") > X statement.

Excellent!

> We have some users who are getting around this limitation by
> using different logins on the same computer to open multiple
> sessions.
...

So your idea of not only counting the number of times the same
user.acct logs on, but also tracking their IP address is sound.
One idea (not tested at all) is:

# Test if this user.acct session is already logged on
if jobcnt("S@":!hpuser.!hpaccount) > 0 then
   echo !hpuser.!hpaccount is already logged on, please try later.
   bye
endif
# This user.acct is not logged on, check IP address under different user
# Note: each session's IP address is kept under /usr/ip/xx.xx.xx.xx
if hpjobtype = "S" and hpremipaddr <> "" then
   if finfo('/usr/ip/!HPREMIPADDR','exists') then
      echo You are logged on as different user via the same IP address,
sorry.
      bye
   endif
   # build the IP addr file to capture this user's IP address
   errclear
   continue
   build /tmp/ip/!hpremipaddr;rec=-1,,f,ascii;disc=1
   if hpcierr > 0 then
      echo Could not build special IP file, please contact Admin Services.
      bye
   endif
endif
...

* To join/leave the list, search archives, change list settings, *
* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *