How to set printer margins?

[Rodolfo Medina <rodolfo.medina@gmail.com>]

Hi all.

With my Samsung ML-1915 I've been printing a .ps file simply with: `lp file.ps'
but part of the text at the beginning of each line is cut off, and so is the
top of the first line.  The same file used to be correctly printed with my old
inkjet Epson.

I wish to set to zero the default printer margins but don't manage to.
Pointing the web browser to: `http://localhost:631' doesn't help because I
don't see any reference to margins there.

I tried to properly edit the file `/etc/cups/ppd/samsung.ppd' with no success.
The file presents the following entry:

*PageSize A4/A4: "<</Policies <</PageSize 7>> /.HWMargins [12.5 12.5 12.5 12.5] /PageSize [595 842] /ImagingBBox null>> setpagedevice"

I changed all occurrences of 12.5 to 0 but the problem remains.

Please help with this issue.  In the internet I couldn't find any further help
apart from the suggestion to edit the ppd file in Ubuntu forums.

Thanks
Rodolfo