User`s guide

4-135
Printer, Plotter, and Spooler Subsystem Programming
How piobe Uses Printer Colon Files
piobe has the ability to generate diagnostic output. A specific example of this diagnostic
output is used in the following discussion to examine the following:
• How piobe uses printer colon files.
• How printer colon file escape sequences are evaluated to resolve path names.
• How printer colon file escape sequences are evaluated to resolve page length.
• How printer colon file escape sequences are evaluated to resolve page width.
This discussion is complex, and is intended for readers that need to understand printer
colon file escape sequences at a low level, perhaps because they want to write their own
colon file for a unique and unsupported printer. Before reading this discussion, you should
be familiar with these topics:
• Printer Colon File Escape Sequences, on page 4-14
• Viewing, Formatting, or Modifying Virtual Printer Definitions, on page 4-129
The following command uses the –a1 flag/argument to request diagnostic data from the
piobe backend. The remainder of the command specifies that the job be processed by the
queue named asc, that three copies of the file named /etc/motd be printed in a 12–point
Courier font rotated 90 degrees, that the job be pre–processed by the pr filter, and that any
messages generated by the job should be mailed to the user that submitted the job.
qprt –a1 –Pasc –fp –z1 –p12 –scourier –C –N3 /etc/motd
Issuing this command results in mail similar to the following being sent to the user that
issued the command:
Message from qdaemon:
=====> MESSAGE FROM PRINT JOB 31 (/etc/motd) <=====
0782–034 Below is the preview information requested with the –a1
flag.
No files will be printed.
PRINTER:
[devices.cat,71,66;IBM 4029 LaserPrinter] (ASCII)
FLAG VALUES:
a=1, b=0, d=a, e=!, f=p, g=1, h=, i=0, j=1, l=48, p=12, q=, s=cou
rier, t=0,
u=1, v=6, w=128, x=2, y=!, z=1, A=1, B=nn, C=+, E=!, G=!, H=, I=,
J=+, L=+,
N=3, O=3, P=ascx:lxx, Q=1, W=!, X=ISO8859–1, Z=+
PIPELINE OF FILTERS:
/usr/bin/pr
–l48
–w128 /etc/motd |
/usr/lib/lpd/pio/etc/pioformat
–@/var/spool/lpd/pio/@local/ddi/ibm4029.asc.lp1.asc:lp1
–!/usr/lib/lpd/pio/fmtrs/piof5202
–l48
–w128
–p12
–scourier
–z1
The mail specifies several items:
• The physical printer that would have been used.
• The values of the flags that pertain to this spooler queue.
• The pipeline of filters that would have been executed.