Inside Macintosh: QuickDraw GX Printing Extensions and Drivers /

Chapter 4 - Printing Messages / Printing Messages Reference

Printing Messages / Device Communications Messages

GXStartSendPage

QuickDraw GX sends the GXStartSendPage message when it's ready to send a page to the printer. You can override the GXStartSendPage message to set up printing for the next page. Your override of the GXStartSendPage message must match the following formal declaration:

OSErr MyStartSendPage (gxFormat pageFormat);

pageFormat

The format for this page.

function result

An error code. The value noErr indicates that the operation was successful.

DESCRIPTION

QuickDraw GX's default implementation of the GXImagePage message sends the GXStartSendPage message to signal that QuickDraw GX is ready to start sending a page to the printer.

The default implementation of this message handles PAP, serial, and not-connected connections. You can override this message to perform tasks such as making sure that the previous page printed successfully and resetting page margins in the printer.

You must forward the GXStartSendPage message to other message handlers so that they can override it. If your override fails, you need to call the GXCleanupStartSendPage function to notify other handlers of the failure. If another handler returns an error, you must undo anything that you've done and return the same error.

SPECIAL CONSIDERATIONS

You never send the GXStartSendPage message yourself.

If you are implementing a nonsupported type of communications connection, you need to perform a total override of the GXStartSendPage message. Otherwise, you need to first forward the message and then perform your tasks.

RESULT CODES

gxSegmentLoadFailedErr	A required code segment could not be found, or there was not enough memory to load it.
gxPrUserAbortErr	The user has canceled printing.

The default implementation of the GXStartSendPage message can also return the communications errors that are listed in Table 4-2 on page 4-42.

SEE ALSO

You can find an example of an override of the GXStartSendPage message in
Listing 3-13 on page 3-39 in the chapter "Printer Drivers."

The GXCleanupStartSendPage function is described on page 5-37 in the chapter "Printing Functions for Message Overrides."

The GXImagePage message is described on page 4-94.

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