Thread View: comp.lang.postscript
2 messages
2 total messages
Started by Peter Kretschmar
Mon, 11 Jan 1993 16:31
How do I read a file from the DEC LN03 PS printer?
Author: Peter Kretschmar
Date: Mon, 11 Jan 1993 16:31
Date: Mon, 11 Jan 1993 16:31
22 lines
1351 bytes
1351 bytes
Hello, I'm posting in behalf of a colleague who hasn't found his way around to Usenet yet. He want's to have a PostScript job running on our DEC LN03 printer to read in a file from disk. He tried to use some code, that worked on a HP printer, connected to a Unix system: (name_of_file) (r) file but this didn't work out with the DEC LN03. He already tried some more obvious variations like giving the full VMS filename (at least, that's what he told me). We don't seem to have much documentation on the printer, and he hasn't got a clue what to change, or if this is possible at all. Any input, especially hints and pointers to more information would be very welcome (I looked through my copy of the PS FAQ already). Thanks in advance, Peter -- Peter Kretschmar psikr01@convex.zdv.uni-tuebingen.de
Re: How do I read a file from the DEC LN03 PS printer?
Author: Stephen Zisk
Date: Tue, 12 Jan 1993 23:26
Date: Tue, 12 Jan 1993 23:26
52 lines
3415 bytes
3415 bytes
In article <psikr01.726769901@convex>,
psikr01@convex.zdv.uni-tuebingen.de (Peter Kretschmar) requested
information on reading files fromn the LN03 and made a comment
about reading on an HP printer.
THE SHORT ANSWER:
What you want cannot be done. I don not know any "standard" PostScript
printers which can read files from their host systems. This would be
possible for certain network-connected printers (although I do not
know of any which implement this), and it would be easy for software-
based rips (e.g. CPSI from Adobe can do this).
THE LONG ANSWER:
The read operator in PostScript allows reading from a file which is
available to the printer. This includes two classes of files:
1.) Attached disks or virtual disks. These can be internal or
external. Many cartridges behave as read-only file systems.
A few printers accept flash-ram cartridges which behave as
read-write file systems. Software rips generally treat host
file systems as attached disks.
2.) I/O devices. currentfile is an operator which allows a
PostScript program to read from the current job stream.
On a level 2 printer, read can be issued against any port.
The simple currentfile case is used commonly in PostScript,
for example to read image data. The general case requires
communication via multiple ports, with some manner of
synchronization if it is to be used generally.
There are two main problems with implementing a printer which can
read from its host's file system:
1.) Establish a communications protocol which is rich enough
to allow file I/O. With network connections (at least TCP/IP,
NETWARE, and Ethertalk over Ethernet, and Localtalk), this is
possible, but a protocol must be chosen, and published, and
some S/W must be written to take advantage of it. For serial
connections, this is problematic, and for unidirectional
parallel, impossible.
2.) Establish conventions for file control. This includes file
names, path names, record conventions, binary interpretation,
and more esoterica (logical names in VMS, aliases on the Mac,
translation of volume letters to network references on the PC,
and so on). If you want to solve this problem in a general way,
good luck! For simple cases, where the characteristics are
tightly controlled, it would be easier, but not too useful.
I hope this clears things up, if only in a negative way.
Stephen Zisk (zisk@adobe.com) Disclaimer: These are my personal views
Adobe Systems Incorporated and do not represent the position of
Eastern Regional Office Adobe Systems Incorporated.
24 New England Exec. Park
Burlington, MA 01803 They pay me but they don't muzzle me!
Thread Navigation
This is a paginated view of messages in the thread with full content displayed inline.
Messages are displayed in chronological order, with the original post highlighted in green.
Use pagination controls to navigate through all messages in large threads.
Back to All Threads