Re: 23.0.50; ps-print-buffer-with-faces hangs on w32

[Jason Rumney <jasonr@gnu.org>]

Lennart Borgman (gmail) wrote:
>>
>> What exactly does this mean?
>>
>> Does any Emacs variable have the value "C:\\PRN"?
>
> The variable `printer' above.
I don't have a variable `printer', is this from an external package you 
have installed?
I do have a variable `printer-name', but it's default value on Windows 
is the device name "PRN", not "C:\\PRN" (which though it looks like a 
file name will still refer to the PRN device under some circumstances in 
Windows, but I'm not sure Windows is consistent about this, and in some 
cases may actually refer to the file, especially if the printer driver 
for your default printer does not expose a standard character device).

>
>> What is a "Windows printer"?
>
> I forgot what these printers are called. It seems like they are called 
> "GDI printers" or "winprinters".
Calling them winprinters suggests that there is something that makes 
them a win over other more functional printers. Really the printer 
hardware is not the issue, often the printer will be better supported by 
Free Software like CUPS than by the manufacturers own Windows drivers, 
so calling them Windows printers is also misleading. What you really 
mean is that the Windows printer drivers that the manufacturer has 
supplied are limited to supporting only GDI based printing, as they do 
not expose a character device (and are connected via USB, so the COM or 
PAR character devices are not automatically available) that could be 
used to print directly to the printer in text mode or whatever command 
language(s) that the printer supports natively (eg Postscript, PCL or 
ESC/P). This problem can often be worked around by sharing the printer 
from Windows, and setting the printer-name within Emacs to the network 
share path of the printer (eg "//localhost/printer").

But it is unlikely that a printer with such limited drivers supports 
Postscript natively, so to use the ps-print commands, you'll need to set 
up a software postscript interpreter such as Ghostscript anyway.