Re: Printing in GTK+

["Carl B. Constantine" <duckwing duckwing ca>]

* Roger Leigh (rleigh whinlatter ukfsn org) wrote:
> "Carl B. Constantine" <duckwing duckwing ca> writes:
> 
> > I have some data I want to print out in my application. How do I do it?
> > To make things a little different, I *might* print to one of those POS
> > type printers (USB) not a regular printer.
> >
> > Pointers? Which classes do I need to use?
> 
> GTK+ itself doesn't currently offer any printing support, so the
> question doesn't really involve GTK+ directly.  You need to either
> 
> 1) Open the printer device (e.g. /dev/usb/lp0) and write data to it.
> 2) Open a pipe to the printer spooler (e.g. lpr -P queuename)
>    and then write the job data and close the connection.

Thanks for clearing this up.

> By a POS printer, I take that to mean a 40 col receipt printer sort of
> thing.  These are basic devices which are basically ASCII thermal
> printers plus some additional control codes and possibly some extra
> bitmap raster graphics mode.  For these you just send the control
> codes inline with the text you're printing to either (1) or (2) above.
> Your program is entirely responsible for the formatting, layout and
> cutting etc.

yes, that's pretty much what I mean. What do I use to do layout and
formatting before dumping to the printer?

Where would I find information on the extra control codes? I'm sure not
all printer manufactureres publish this sort of thing. How does that
work with CUPS?


> For the work I do, I send jobs to a receipt printer via CUPS.  After
> completion of a transaction, the receipt gets printed after a barely
> noticeable delay (< 0.5s).
> 
> 
> Your best bet is to use a spooler.  This also makes networked
> operation totally transparent, and is far more flexible.  You can use
> libcups, lpc or lpstat etc. to get a list of all available printers if
> the user needs to choose one.

Ok, so I probably will use a print spooler (CUPS), what do I need to do?
I'll look at the CUPS docs, but some fast direct pointers are nice.

Thanks in advance.


-- 
 .''`.      Carl B. Constantine
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