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CDE/Motif PST
CDEnext
X P
RINT
D
RIVER
I
NTERFACE
9.1
Xp Print Driver Overview
9.1.1
PURPOSE
This chapter describes the interfaces used to integrate the print drivers into a server with the Xp extension.
This section includes descriptions of the functions a driver is required to implement in order to cooperate
with the Xp extension, and descriptions of some utility functions available for the convenience of driver
writers. Not covered here are normal DDX driver interfaces for core X functionality.
9.1.2
DESCRIPTION
The X Print server is simply an X server with the Xp extension. The drivers effectively provide a mapping
from most X protocol rendering operations to a form understandable by a particular class of printer. The
drivers are much like the hardware-specific display drivers in any other X server, but need to have some
slightly different and extended capabilities in order to cooperate with the Xp extension, and with the
configuration capabilities exposed via the Print Dialog Manager and its associated setup dialogs.
9.1.3
DEPENDENCIES
The print drivers are tightly coupled with the X server itself, and the initial sample print server will be
based on the X11-R6 server as supplied by the X Consortium.
9.1.4
ISSUES
9.2
X Print Driver Initialization
9.2.1
Information Available During Initialization
The driver has the following practical sources of information during its initialization:
x
Command line arguments - The driver's initialization routine is passed argc and argv corresponding to the
arguments passed on the command line to the server.
x
Information in the ScreenRec - The driver's initialization routine is passed a pointer to a ScreenRec
containing potentially useful information. In particular the width, height, mmWidth, and mmHeight fields
are filled in with the maximum potential dimensions prior to the calling of the driver's initialization routine.
x
Driver-specific configuration files - The driver can attempt to read information from on-disk files it may
expect to be in place on the system.