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Path: utzoo!mnetor!uunet!husc6!rutgers!iuvax!pur-ee!uiucdcs!bradley!john
From: john@bradley.UUCP
Newsgroups: comp.bugs.sys5
Subject: Re: SysV lp spooler a security hole
Message-ID: <15000001@bradley>
Date: Sat, 12-Sep-87 17:21:00 EDT
Article-I.D.: bradley.15000001
Posted: Sat Sep 12 17:21:00 1987
Date-Received: Tue, 15-Sep-87 03:54:58 EDT
References: <313@pvab.UUCP>
Lines: 30
Nf-ID: #R:pvab.UUCP:313:bradley:15000001:000:1578
Nf-From: bradley.UUCP!john    Sep 12 16:21:00 1987


kitty.UUCP!Larry (Larry Lippman) Writes:

|1.	There is no reason why more than one printer name cannot be associated
|with _one_ physical printer using _one_ physical I/O port.  The usefulness
|here is to invoke the _same_ printer in a different fashion merely by
|specifying a different printer name as an lp(1) argument.  For example,
|one name will invoke a laser printer for landscape printing (132 cols wide),
|with another name will invoke the laser printer for portrait printing (80
|cols wide).  The different setup commands for the laser printer are contained
|in the individual /usr/spool/lp/interface/printer_name shell scripts.

I can think of one reason NOT to do just this....The lpsched program 
just checks to see if a job is currently printing on the named printer.  It
DOESN'T check to see if the physical port is busy.  At least on SYSV 2.0, 2.1
			    ---------------------

So if you haven't figured this one out....If you have two printers with 
different names (lp1 and lp2) connected to the same physical I/O port (tty11)
then lpsched will print both jobs at once...

I patched our lpsched program so that it will check to see if there are ANY
printers busy which are connected to the  same physical port as the requested 
printer.  Other than that, I really like setting up printers this way....
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv
John Lengeling			UUCP: {cepu,ihnp4,uiucdcs}!bradley!john
Bradley University		ARPA: cepu!bradley!john@CS.UCLA
Text Processing 		PH: (309) 677-2230
Bradley Hall Room 6F
Peoria, IL 61625