Specifications

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Guide to Printers and Printing
• mn – Device name
• mq – Queue name (name of a queue stanza in /etc/qconfig)
• mv – Virtual printer name (name of a corresponding device stanza in /etc/qconfig)
These file virtual printer attributes are initialized by the piodigest command at the time the
queue and virtual printer are created. The combination of the five is unique in the virtual
printer database.
For this queue, the value of mt.md.mn.mq.mv is ibm4029.asc.lp1.asc.lp1. Thus the value
of the –@ flag to pioformat becomes
/var/spool/lpd/pio/@local/ddi/ibm4029.asc.lp1.asc.lp1, the full path of the
digested database file defining the virtual printer associated with this queue ( asc ).
The ’–!’ is a second flag to pioformat, specifying the full path name of the
device–dependent formatter to be loaded, linked, and driven at runtime by the formatter
driver, pioformat. It is here that you can see how and where the runtime connection
between these two modules occurs.
The value of the –! flag is specified by the concatenation of the remainder of the printer
colon file escape sequences shown in the formatted form of the ia attribute, beginning with
%Idf and ’/piof5202 –l’.
The value of %Idf in defined in the colon file as %I@4/fmtrs. The @4 is an automatic
variable whose value is /usr/lib/lpd/pio, so %Idf resolves to
/usr/lib/lpd/pio/fmtrs. The ’piof5202 –l’, without the single quotes, is appended to
this string, so the value of the –! flag to this point becomes
/usr/lib/lpd/pio/fmtrs/piof5202 –l. The –l is a flag to piof5202, the
device–dependent formatter for an ASCII data stream on an IBM 4029 LaserPrinter, that
specifies page width in characters.
The calculation of the argument to the –l flag, %IwL, is described in Appendix A. Calculating
Page Length Using Printer Colon File Escape Sequences on page A-1.