Printing

TCM has a range of printers ranging from A4 black and white laser printers to A0 colour inkjet. All accept PostScript (levels 1 to 3), all save the A0 printer support duplexing. All are accessible from laptops on the wireless network via IPP and plover.

Queue Names

Queue Name      Printer     Location

{default}, ps2  HP 602      Coffee Area

    ps          HP 4250     Rm 523

    psc         HP M651     Coffee Area
               (A4 colour)

    psca3       HP M750     Rm 523
               (A3 colour)

    psca0	A0 Colour   Rm 523
		DesignJet
		1055 PS

All printers default to a paper size of A4. To use the A3 capability of the A3 laser printer, the job must specify it explicitly. Similarly for the A0 printer, which will accept any page size up to a width of three feet.

All printers also print plain text, along with the ill-defined language PCL5.

Their current supplies status can be determined from their status page.

lpr and duplexing

The traditional way of printing in the UNIX world is via the lpr command. Whereas modern applications have GUI dialog boxes which let one select paper size, duplex options, etc., lpr does not. It simply passes the file on to the printer. If the file is inappropriate, lpr will not notice. Plain text and PostScript are the only supported file types.

To print a colour PostScript file to the printer psc:

$ lpr -Ppsc file.ps

To print a colour PostScript file duplexed to the printer psc:

$ duplex -Ppsc file.ps

To print a plain text file to the printer ps:

lpr -Pps file.f90

And to do so more prettily:

a2ps -Pps file.f90

To print other non PostScript files, such as jpeg, eps or pdf file, convert to PostScript first. There are many ways of doing so, but bmp2eps -p, eps2ps and pdf2ps are possibilities for the examples given.

lpq and lprm

The lpq command allows one to check the progress of a print job. In its most command use:

$ lpq -Ppsca0

The lprm command allows one to remove print jobs:

$ lprm -Pqueue jobno

gv

The program gv is a useful way of previewing on screen a PostScript file. It has one surprise in store. It sets its paper size from the DSC comments at the beginning of the file. The printer will ignore these, and set its page size from any setpagedevice command in the file. Although the DSC comments should be consistent with the setpagedevice command (and they exist so that programs like LaTeX can quickly determine the size of the image in a PostScript file without having to parse the whole document), there is no guarantee.

$ gv file.ps &

Problems

We currently limit print job sizes to about 200MB, as anything bigger than this is usually a mistake.

It is possible for a printer to crash. If the lpq command complains that the printer is unreachable, this has happened. If the lpq command still regards the printer as being unavailable even after the printer has been power-cycled, then it may be necessary to restart the print queue. Anyone can do this:

$ cupsenable psca3

or whatever queue is appropriate.

It could be that a specific job is causing problems. If so, anyone can removed anyone else's job with lprm. Using the job number reported by lpq:

$ lprm -Pqueue jobno

Paper

Paper lives in the cupboard beside the black and white photocopier by the side of room 535. If this is empty, the secretaries should be told, and/or a PhD student found and sent down to Reception to collect a box or two. (Boxes being five reams, a ream being 500 sheets (or twenty quires).)

One can perform entertaining calculations: An A0 sheet is one square metre, so an A4 sheet is one sixteenth of a square metre. An A4 sheet of 80gsm paper therefore has a mass of 5g. So a ream has a mass of 2.5kg, and a box a mass of 12.5kg.