[Info-vax] IPP utiltiy

[Louis Krupp]

On 5/5/2021 3:20 PM, Mark Berryman wrote:
> On 5/5/21 1:49 PM, Louis Krupp wrote:
>> On 5/5/2021 10:19 AM, Mark Berryman wrote:
>>> On 5/4/21 2:49 PM, Simon Clubley wrote:
>>>> On 2021-05-04, Mark Berryman <mark at theberrymans.com> wrote:
>>>>> Based on feedback, it would appear that a number of the printers out
>>>>> there are designed more for mobile printing than desktop printing. 
>>>>> This
>>>>> is indicated by the document formats they support. Typically, such
>>>>> printers return a supported document format list similar to the 
>>>>> following:
>>>>>
>>>>> application/vnd.hp-PCL: this is HP?s Printer Control Language.  It is
>>>>> text with escape sequences although binary data can be included when
>>>>> graphics are involved.
>>>>>
>>>>
>>>> Just for completion, there are multiple PCL versions around.
>>>>
>>>> Is there any indication of which PCL version(s) this covers ?
>>>
>>> Yes.  Each printer will have some attribute indicating which version 
>>> of the various protocols it supports.  Mine, for example, claims PCL 
>>> 6 support.
>>>
>>
>> FWIW:
>>
>> PCL 5, to my knowledge, is a superset of PCL 4, which is a superset 
>> of PCL 3, and so on. PCL 6 (also known as PCL XL) is very different.
>>
>> I haven't seen any glaring inaccuracies in the Wikipedia entry:
>>
>> https://en.wikipedia.org/wiki/Printer_Command_Language#PCL_levels_1_through_5_overview 
>>
>>
>> (I worked on embedded PCL 5 and PCL 6 interpreters about twenty years 
>> ago.)
>
> As far as I know, PCL 6 "enhanced" is PCL XL.  PCL 6 "standard", 
> frequently written as simply PCL 6, is the same as PCL 5e (or PCL 5c 
> if color).
>
> As an example, my printer claims PCL 6, and has properly printed every 
> PCL file I've thrown at it, most of which were PCL 3.
>

Basically, PCL 6 *is* PCL XL.

I also have a printer that claims PCL 6 support. When I printed a Word 
document and selected "Print to file," I got this:

%-12345X at PJL JOB
@PJL SET JOBATTR "OS =Windows"
@PJL SET JOBATTR "OS Version = Windows 8.1 6.3.9600.1"
@PJL SET JOBATTR "Render Type = InOS"
@PJL SET JOBATTR "Render Name = HP PCL6 Class Driver"
@PJL SET JOBATTR "Render Version=6.3.4.1"
@PJL SET COPIES=1
@PJL SET QTY=1
@PJL SET RESOLUTION=600
@PJL ENTER LANGUAGE=PCLXL
) HP-PCL XL;2;0;Comment Copyright(c) 1999-2011 Hewlett-Packard Corporation
<stuff in binary>LETTER

The first few lines are in PJL, or Printer Job Language. The stuff in 
binary looks like this when run through the Linux octal dump (od) 
command with the flags "-a -A none":

     C   o   r   p   o   r   a   t   i   o   n  nl   Q   X stx   X
  stx   x  ht   @ nul   x ack   @ etx   x  si   A   @ nul   x  bs
    @ soh   x stx   H   @ soh   x   &   @ nul   x   (   @ nul   x
    4   @ nul   x   (   H   @ ack   L   E   T   T   E   R   x   %
    C   U nul nul nul   ? nul nul nul   ?   x   +   w   @ soh   x
    G   q   @ soh   x   H   r   @ soh   x etx   j   @ nul   x   -
    x   @ nul   x   -   |   a   H   @ stx   F   0   x   (   @ nul
    x   )   O   A   &   8   x   '   P   z   &   8 nul nul nul nul

It's mostly binary, glorious binary. There are none of the escape 
sequences that characterize PCLn (where n <= 5), like this file I found 
online:

esc   &   l   3   A esc   &   l   0   o   0   l   6   d 3   E
  esc   *   p   0   Y esc   *   v   0   t   0   n   0   O esc   (
    8   U esc   (   s   0   p   1   0   h   1   2   v   0   s   0
    b   3   T esc   *   p   2   9   9   x   7   0   Y   D   S   I
   sp   T   E   S   T  sp   L   E   N   D   E   R  sp   F   O   R

I'm having a hard time finding a PCL6 reference manual online.

Two things about your printer:

1. I'm sure your printer supports PCL6. It also supports PCL5 and its 
ancestors.

2. PCL6 support might or might not even matter. It might be there 
because printer manufacturers believe that the more page description 
languages (like PCL5, PCL6, XPS) the printer supports and the more of 
them are listed on the box, the more likely you are to buy the printer. 
I worked for a company that built PDF support into some of its printers; 
if the driver could send a PDF file to the printer, the printer could 
print it. This required the printer to have its own disk drive so it 
could spool the PDF file; if you've worked with PDF internals, you'll 
know that you might be able to print the first page right away, but to 
print anything else, you have to read the directory that's at the *end* 
of the file. I've never had a problem with opening a file with Adobe 
Acrobat Reader and letting it talk to the printer, but I'm sure that in 
some situations, it's good to bypass that.

Louis