XpCreateContext - Creates and initializes a new print context.
cc [ flag... ] file... -lXp [ library... ]
XPContext XpCreateContext ( display, printer_name )
Specifies a pointer to the Display structure; returned from
The name of a printer on display. String encoded as
XpCreateContext creates a new print context that is initialized with
the default printer attributes and other information available for
printer_name on display. A print context maintains the printer name,
print attributes, font capabilities, print (rendering) state and
results, and is the object upon which the Xp calls act.
If the library fails to generate a new print context-id, a value of
None is returned, otherwise a print context-id is always returned. If
printer_name is invalid, a BadMatch is generated later by the X Print
A call to XpGetPrinterList will return a valid list of values for
printer_name. All printer name values in the X Print Service are
encoded as COMPOUND_TEXT (of which the ISO-8859-1 code-set is a proper
As soon as a print context is created, the print attributes in it can
be accessed and modified by calling XpGetAttributes and
XpSetAttributes, and the event selections in it can be modified by
calling XpSelectInput and XpInputSelected. Other Xp calls that
explicitly take a print context-id as a parameter will operate directly
on that print context. All Xp and X calls without a print context-id
parameter (for example, all rendering oriented calls like XpStartJob
and XDrawLine) require that a print context be set on the display
connection (see XpSetContext). Failure to set a print context prior to
calling a print-context-dependent call will result in the generation of
an XPBadContext error.
The XPContext returned by XpCreateContext is an XID, and can be used to
set the print context on display connections by calling XpSetContext.
The XPContext id can be shared between processes and display
connections. It is the responsibility of the clients sharing a print
context to coordinate their usage of the context; for example they must
ensure that in-use print contexts are not prematurely destroyed.
The context_id remains valid for all clients until 1) the client
creating the print context closes its display connection, or 2) any
client calls XpDestroyContext. The context_id can be kept valid after
the creating client's display connection closes if XSetCloseDownMode is
called on display with RetainPermanent or RetainTemporary.
After creating a print context, and possibly modifying the XPDocAttr
attribute document-format using a value from the list of available
formats shown in the XPPrinterAttr attribute document-formats-
supported, the application must query the X Print Server via
XpGetScreenOfContext for the screen that has been associated with the
print context, and then create all server resources that will be used
in the print job on that screen. Failure to do so will result in
When XpCreateContext is called, the client's locale (see
XpSetLocaleHinter) is included in the request as a "hint" to the X
Print Server. If supported by the implementation, the X Print Server
will use the hint to initialize the attribute pools with any localized
attribute values (for example, the human readable XPPrinterAttr
attribute "descriptor" may be available in several different languages,
and the hint will be used to select one). If the X Print Server cannot
understand the hint, the X Print Server chooses a default value.
This function can generate a BadMatch error if the specified
printer_name does not exist on display, or if the print server could
not interpret the code set specified in printer_name.
BadMatch The value specified for doc_fmt is not valid for the
current document type or the value specified for
drawable is not valid for the print context and print
XpDestroyContext(3Xp), XpGetAttributes(3Xp), XpGetPrinterList(3Xp),
XpGetScreenOfContext(3Xp), XpInputSelected(3Xp), XpSelectInput(3Xp),
XpSetAttributes(3Xp), XpSetContext(3Xp), XpSetLocaleHinter(3Xp),