You might check this out. http://www.linuxprinting.org/ * Brian Durant (durant@cbn.net.id) [020531 23:06]: ::Is there someone out there that can explain the relationship between CUPS, ::Gimp-Print, Turbo Print, etc.? I am using SuSE 7.3 Pro and still trying to ::get my new Epson Stylus C80 to work. I think that somewhere, I am lacking ::some information to understand how printing works under SuSE. I need to ::understand why you need both CUPS and Gimp-Print, why Turbo Print requires ::Ghostscript, etc. Can all of the above coexist? I do however, realize that ::some of the above are GPL and others are commercial products, so we don't ::need to get into that. Is there a URL that will cover this? -=Ben --=====-----=====-- mailto:ben@whack.org --=====-- If it's true that our species is alone in the universe, then I'd have to say that the universe aimed rather low and settled for very little. -GC --=====-----=====--

Is there someone out there that can explain the relationship between CUPS, Gimp-Print, Turbo Print, etc.? I am using SuSE 7.3 Pro and still

get my new Epson Stylus C80 to work. I think that somewhere, I am lacking some information to understand how printing works under SuSE. I need to understand why you need both CUPS and Gimp-Print, why Turbo Print requires Ghostscript, etc. Can all of the above coexist? I do however, realize

I'll probably get some of this wrong, but essentially... Printing is a multistage process in linux. First, the application, e.g. Mozilla, StarOffice, KWord, produces PostScript output and uses a command called lp to send this to a printer, typically with some commandline options. lp was originally a BSD unix command that sent the file to be dealt with by the lpd daemon, a background process. Originally lpd would have handled a queue of jobs going to the printer. All of them would be PostScript files and the queuing (or spooling) system would make sure you didn't try to print two jobs at once. Several intermediate stages have been introduced. First, if the printer wasn't a true PostScript printer (like most inkjets) then instead of spooling the PostScript directly to the printer, it would get sent first to Ghostscript, which can create a raster image suitable for printing, then to a printer driver, that can send the raster image to the printer. gimp-print is an example of a printer driver. Second, there are usually some simple filters so that if you try to send something other than PostScript, it gets turned into PostScript before being sent on to the printer (or ghostscript). a2ps is an example of one that can be used to convert ascii to PostScript. These filters allows things like # man lp | lp to work seemlessly (if you don't know how to use man -t). Third, there are some limitations on BSD lp. CUPS and (I think) turboprint and foomatic give greater functionality by allowing you to print to networked printers, specify default printer settings and resolutions, etc., and I think handling any filtering for you. CUPS and foomatic need to know what parameters to send to ghostscript, e.g. so that it knows the page size, horizontal and vertical resolution, papertype, etc. for the printer that the job is going to get sent to. These are stored in a PostScript PPD file. It makes sense to distribute the PPD files along with the printer-driver (e.g. gimp-print) rather than with CUPS or foomatic, because there is no point in having a PPD file for a printer that you don't have a driver for. JDL Brian Durant wrote: trying to that

some of the above are GPL and others are commercial products, so we don't need to get into that. Is there a URL that will cover this?

Cheers,

Brian

-- Non enim propter gloriam, diuicias aut honores pugnamus set propter libertatem solummodo quam Nemo bonus nisi simul cum vita amittit.