Specifications

4-4
Guide to Printers and Printing
Virtual Printer Definitions and Attributes
A virtual printer definition is a file that pairs the attributes or characteristics of a specific
printer with the attributes of a specific data stream type. If a specific printer supports more
than one data stream type, you must create a virtual printer definition, pairing the attributes
of the printer with each data stream type. Thus, if a printer supports both ASCII and
PostScript data streams, you must create two virtual printer definitions for the printer.
The colon file stores the virtual printer definition for a printer or plotter. Colon files reside in
the predefined and customized database directories. The printer backend uses the attribute
values stored in colon files to format print requests.
All attribute values reside in colon files as character strings, regardless of whether they
represent strings, integers, or Booleans. An attribute value can contain embedded
references to other attribute values or embedded logic that dynamically determines the
content of the value.
For more information on colon files and how embedded references and logic are used in
attribute strings, see Printer Colon File Conventions on page 4-21 and Printer Colon File
Escape Sequences on page 4-14.
Working with Virtual Printer Attributes
The commands used to create a virtual printer (the mkvirprt or smit virprt commands)
copy a predefined virtual printer definition and create a customized virtual printer definition
for the specified queue and queue device. The attribute values in the custom definition can
be further changed, with the chvirprt or smit lsvirprt commands.
You must create a virtual printer for each data stream type supported by a specific printer
device. The supported data stream types include:
Data Stream
Type
Code for Attribute
Name/Value
Description
asc a Extended ASCII
pcl c Hewlett–Packard PCL
630 d Diablo 630
gl g Hewlett–Packard GL
p Pass–through (sent to printer unmodified)
ps s PostScript
855 a Texas Instruments 855
kji k Kanji
When you use the mkvirprt or smit virprt command to create a virtual printer, the system
prompts you to select the desired printer from a list of defined printers. If you have just
configured a printer port for a new printer, select the new printer port. When the virtual
printer command is executed, the system creates a print queue and copies the colon file for
the selected printer in the predefined database directory, /usr/lib/lpd/pio/predef/*, to the
customized database directory /var/spool/lpd/pio/custom/*.
Note: If no flags are specified, the mkvirprt command becomes interactive.
Use the chvirpt or smit lsvirprt command to change or further customize the attribute
values stored in a virtual printer definition. To change an attribute value with smit lsvirprt,
enter attribute_name = attribute_value with no spaces on either side of the = (equal) sign.
Each attribute name in a virtual printer definition must be unique. Attribute names can
contain the characters a through z, A through Z, 0 through 9, and _ (underscore). Attribute
names must not begin with a numeral. All attribute names must be two characters long,
except for group header attribute names, which can be five characters long.