Solaris print filters for postscript files
Contents:
As UNIX-like systems become more prevalent in this world of cheap computing,
more and more users will be faced with the fact that UNIX tools speak
postscript when they want to print. In addition, anyone doing research
in advanced computer topics will find that postscript is the format of choice
(far above and beyond that of M$ Word and PDF). SO, if you have a printer
that does not understand postscript, which is likely unless you own an
expensive printer, you need to figure out how to print as easily as possible.
Most likely you have discovered that ghostscript will convert to something
that personal printers understand (PCLn on HP printers for example).
Since you can use ghostscript to convert the postscript to a usable format,
the next step is to make it as convenient as possible to do so. Solaris has
the capability to configure print filters that will automatically
convert file formats to make the print job input format equivalent to one that
the printer understands.
In practice this is how Solaris print filters work:
- User submits print job using the lp mechanism
- Solaris examines the file type (as file(1) would, presumably)
- Solaris compares this to the types of files that the physical printer
accepts
- If they do not match, it tries to use any combination of registered
print filters to obtain the correct format
A print filter is basically a mechanism that has an input type
(postscript for example), an output type (PCL) and the command to run to
accomplish this transformation. Usually the input and output will be sent
through pipes. So, you would setup the command to run ghostscript with
whatever flags are necessary plus the flags to indicate that the input is
coming from stdin and the output is going to stdout
The print filter is basically a file in a format that Solaris understands. In
this you indicate the input/output types, the command and other options. This
file is then presented to the OS using the lpfilter(1M) command, at
which time it will be a possible filter for any new print jobs. It is
possible to restrict the filter so that it is only used by certain printers on
the system.
To convert postscript to another format you will need ghostscript installed.
This procedure has been tested on Solaris 2.5.1 and 2.6, so it will probably
work on 2.4 or greater, and maybe even 2.x. Ghostscript must support an
output type that your printer understands.
First you need to create a print filter file. You can copy an existing one
from the files in /etc/lp/fd/. Here is the the one I use to do
straight postscript-to-PCL conversion (PCL is what HP printers understand):
ps2pcl.fd
Input types: postscript
Output types: PCL5
Printer types: any
Printers: nuts
Filter type: slow
Command: /usr/local/bin/gs -q -dSAFER -dNO_PAUSE -sDEVICE=ljet4 -r600 -sOutputFile=- -
See the ghostscript documentation to decide which flags are correct for you.
Notice the the output file is ``-'', which is stdout and the input
(last parameter) is also ``-'', which is stdin. The input type
(first line) is a string that Solaris uses, postscript and simple are the only
ones that are probably useful; simple being plain text. The input type may
somehow correspond to the types that the file(1) command spits out,
but I have not verified this. The output type is arbitrary and is used to
match the type that you say the physical printer can understand; we
will discuss this below. You can restrict the filter to be used only on
certain print queues using the ``Printers'' line. I am not sure what effect
the ``Filter type'' has, but running a program like ghostscript to do the work
is definitely slow!
Next, you need to register this print filter with the OS. Using the
lpfilter(1m) command, we register it and assign it a name as follows:
# lpfilter -f ps2pcl -F /etc/lp/fd/ps2pcl.fd
The first flag (-f) and its parameter tell the filtering system the name that
we want to use to refer to this specific filter in the future. The second
flag (-F) is the file which contains the print filter information; this is the
file that you have just created. The print filter is now registered. You
need to rerun this command if you make any changes that you make to the filter
file.
You can use the command lpfilter -f all -l to list all print filters
currently registered in the system. You will probably want to pipe the output
to more since even the vanilla Solaris install has many pre-installed
filters.
Finally, you need to make the physical printer input types line up correctly
with the filter. You should first create a printer using either
admintool(1m) or lpadmin(1m). Regardless of which way you
choose to setup the printer, you need to run lpadmin with the -I flag
to indicate the input types. To make a newly created printer named ``nuts''
use the print filter that we added above, we execute the following command
(this assumes you already created the printer):
# lpadmin -p nuts -I PCL5
It may be sufficient to do it in one step:
# lpadmin -p nuts -i /dev/bpp0 -I PCL5
This creates a printer called "nuts" which is connected to the device at
/dev/bpp0 and accepts only PCL5 input.
The type that you put after the -I should match the string you indicate on the
``Output Types'' line of the print filter file. In this case, we used
``PCL5'' in both places. This is a custom string, so you can use whatever
name you wish as long as it does not conflict with one already being used in
the system.
Print something! One easy way is to start a web browser and print something.
Make sure that the print job goes to the correct printer (although this
printer is probably the default). Solaris should print a header page and then
the contents of your document. On my system it also spits out a blank page at
the end of each job (so recycle it somehow!)
Read the document carefully!
- How do I get rid of the banner page?
- Edit the file in /etc/lp/interfaces which corresponds to
the printer you want to fix this on. Around line 332 there is a line
that says nobanner="no". Change it to nobanner="yes".
That's all, it will never spit out a banner page.
- How do I get rid of the blank trailing page after each print job?
- Edit the same file as in the previous question
(/etc/lp/interfaces/nuts for example). Around line 992 change
the echo statement in the then statement:
if [ -n "${FF}" -a "no" = "${nofilebreak}" ]
then
echo "${CR}\c"
# echo "${CR}${FF}\c"
fi
Here are some print filters that I made for convenience:
- ps2up2pcl.fd
- Changes the postscript input to print two pages on each sheet of paper
and then sends that to ghostscript. You need the
psutils package.
- ps4up2pcl.fd
- Changes the postscript input to print four pages on each sheet of paper
and then sends that to ghostscript. You need the
psutils package.
Comments/Questions:
ussn@toocool.calpoly.edu
IMPORTANT NOTE: The people who receive mail on the ``ussn'' alias are
students at the university, and are not paid to provide support. If you are a
student of Cal Poly we will do everything we can to help you resolve your
problem. If you are not affiliated with Cal Poly we probably won't have time
to help unless your problem is fairly common or straight forward.
Written By: Brian Kurotsuchi
$Id: solaris-printing.html,v 1.3 1999/04/27 00:27:26 bkurotsu Exp $
( 
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as of 06/01/98