JMP> LPD Job submission mapping

JMP> LPD Job submission mapping

JK Martin jkm at underscore.com
Tue Mar 11 21:34:38 EST 1997


Ron,


Since we live and breath (and die?) in the Unix environment every day,
perhaps we should respond to your question:


> My understanding is RFC 1179 specifies that the Data File and Control
> File may be sent in any order but most implementations send the Data
> File first.  I do not know of a method to reverse the order.  Maybe 
> a Unix expert can help.


Put simply, there is no real way to "reverse the order"...at least with
respect to the protocol.


The LPD protocol (aka RFC 1179) was NOT designed in a vacuum.  It was
designed as part and parcel of the LPD daemon environment; that environment
expected to FIRST spool all components of the submitted job (one or more
data files, followed by one control file).  So, if you have the luxury
of spooling all these components, then of course you can "reverse the order".


Of course, given the typical printer implementation (ie, no disk, etc),
this is not possible.


LPD would work SO WELL if only the control file were always transmitted
first.  If this were true, then the notion of extending LPD to improve
network printing would be a real possibility.


In the category of "Fun Things to Know and Forget":  in our travels,
only OS/2 2.1 sends the control file before the data file(s).  I wonder
how many LPD daemon systems mess up as a result of this...


	...jay



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