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CDE/Motif PST
CDEnext
D
T
P
RINT
D
IALOG
M
ANAGER
5.1
Overview
PURPOSE
A Print Dialog Manager (PDM) is a process separate from the X Print Server and X Printing Application
that provides printer-specific and spooler-specific setup GUIs. An application could choose to understand
and display such GUIs itself, but is advised to offload the task to a PDM so that new printers and spoolers
can be supported by providing new PDMs, rather than requiring changes to all applications.
Within the X Print Service, a standard "Print Dialog Manager Selection Protocol" is described in the
functional specification for
XpNotifyPdm
. This protocol allows an X Printing Application to engage a
PDM.
This chapter describes the CDEnext implementation of a PDM that uses the PDM Selection Protocol. The
CDEnext implementation involves a Print Dialog Manager Daemon (PDMD) executable dtpdmd which is
initially engaged by the protocol, and it then determines which PDM is needed and starts it on behalf of the
application. Within CDEnext, the executable dtpdm is the general purpose PDM that the dtpdmd can start.
Printer Vendors can choose to introduce new GUIs by: 1) developing their own PDM implementation that
conforms to the PDM Selection Protocol, or 2) develop a PDM that can be started by the dtpdmd, or 3)
possibly (is vendor dependent) integrate new shared or dynamic libraries into the dtpdmd. We recommend
approach #2.
DESCRIPTION
The dtpdm executable implements a reasonably general-purpose print dialog manager capable of providing
dialogs suitable for a number of different printers, but specifically tuned to the needs of the two reference
printers, the PCL based HP DeskJet 1600C, and the Postscript based Sun SPARCprinter 2. The dtpdm uses
the attributes (see
XpSetAttributes
) of the particular printer to provide a limited amount of automatic
configuration of the options displayed in its printer setup dialog. The dtpdm's job setup dialog is designed
for use with the lp spooler.
The dtpdmd executable implements a PDM startup mechanism. This two-layer mechanism means that the
PDM Selection Protocol, PDM selection and startup, and security concerns can be delt with by the dtpdmd,
and that resulting PDMs called by the dtpdmd are left with the minimal and simple task of displaying GUIs.