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David Brook wrote: > > I have been unable to find the answers to such practical issues as how > it can resolve two or more concurrent print requests from networked > hosts without interleaving or even interprinting on the same pages, what > happens if a spooling host dies 'mid spool', how do you kill off a 'bad' > print job etc. etc. - loads of practical issues spring to mind. Network printers usually present as a BSD style print queues, so they accept "print jobs", and the queue is full till that job is complete. The old HP JetDirect print servers (and HP printers with them built in) use to "round robin" requests. So if you had two machines connected wanting to send stuff it would print one (complete) job from A, then one from B, then one from A, then one from B. I'm not sure how this was implemented in detail, as I never had one busy enough for it to be an issue, I assume it must of have some way of slowing or holding open incoming print requests whilst it was busy printing. So it isn't absolutely necessary to have a print server. On a GNU/Linux network using CUPS you can add the (network) printer to one box, and it will queue requests, whilst advertising that printer to all CUPS clients on the network. Windows print server do something similar, and can be access from GNU/Linux. But the last two set-ups assume you have a server always on to talk to the network printer, for small networks it is easier just to add the printer to all the machines, but not any good where you could have a rogue print job and not get an answer by shouting "who is using the printer?". Some printers have enough memory to have a queue inside the printer, but that tends to be high end printing equipment. I remember one, which you told it your email address, and you could scan documents in the printer and email them to yourself. Or straight out of the company network - industrial espionage made easy - if you preferred or entered your email address wrong. -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html