PPR: PPR as an import filter for CUPS

[David Chappell]

On 06/17/2014 09:50 AM, Rich Mellor wrote:
> Hi,
>
> I came across an old (2009) mailling list where someone had asked 
> whether the filter_dotmatrix could be ported to be used with CUPS.
>
> I wondered whether any work had ever been done on this, as I am 
> looking into the possibility of creating a small printer box, based 
> around the Raspberry Pi, which would capture ESC/P data from a 
> centronics port, and then convert it and print it out on a modern 
> printer.
>
> I know PPR already has the ability to convert ESC/P (2) data to 
> Postscript format.
>
> The main problem is probably that the filter needs to output as UTF-8 
> for CUPS.
>
All you need to use a PPR filter with CUPS is a simple shell script. 
This script would take the parameters supplied by CUPS, extract any 
information needed by the PPR filter, and run it. It should also copy 
its stdin to a temporary file and supply that file to the PPR filter as 
stdin. This is necessary because PPR filters are allowed to assume that 
stdin is seekable.

So, there really isn't any work to do. Somebody just has to try it.

As for UTF-8, CUPS neither knows nor cares how the characters are 
encoded within the Postscript file.