Managing printer driver private data

Set and get some driver private data in your callback functions. More...

Functions
void	caps_drv_private_set (struct caps_drv *cdrv, void *private)
void *	caps_drv_private_get (struct caps_drv *cdrv)

Detailed Description

Instead of using global data, you can collect all your private printer driver data and information into a structure and let libcapsdriver forwards a pointer to your callback functions.

Each callback function comes with an anonymous pointer to private data you can use to run your driver.

The caps_drv_private_get() function can be used instead in the absence of this anonymous pointer.

Attention

The anonymous pointer in the caps_generic_driver::init callback is special. Refer Callback init() for details.

Function Documentation

caps_drv_private_set()

void caps_drv_private_set	(	struct caps_drv *	cdrv,
		void *	private
	)

Set a hint to the private data of your driver implementation

Parameters

[in]	cdrv	libcapsdriver handle
[in]	private	The hint to your private data

This hint is used as the ud parameter in all further callbacks.

Can be called in the caps_generic_driver::init() callback, because it provides you with the libcapsdriver handle as well.

This function is the opposite of caps_drv_private_get()

caps_drv_private_get()

void * caps_drv_private_get

(

struct caps_drv *

cdrv

)

Get the hint to the private data

Parameters

[in]

cdrv

libcapsdriver handle

Return values

PRIVATE	The hint to the private data
NULL	Not yet set

This function is the opposite of caps_drv_private_set()