LTWAINSOURCEINFOCALLBACK Function

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#include "lttwn.h"

L_INT pEXT_CALLBACK YourFunction (hSession, pSourceInfo, pUserData)

HTWAINSESSION hSession;	/* handle to an existing TWAIN session */
pLTWAINSOURCEINFO pSourceInfo;	/* pointer to the LTWAINSOURCEINFO structure */
L_VOID * pUserData;	/* pointer to additional parameters */

Called for each available TWAIN source installed on the system. The address of this callback is passed as an argument in L_TwainGetSources.

Parameter	Description
hSession	Handle to an existing TWAIN session. This handle is obtained by calling the L_TwainInitSession function.
pSourceInfo	Pointer to the LTWAINSOURCEINFO structure that contains the name of the TWAIN source retrieved.
pUserData	A void pointer that you can use to access a variable or structure containing data that your callback function needs. This gives you a way to receive data indirectly from the function that uses this callback function. (This is the same pointer that you pass in the pUserData parameter of L_TwainGetSources.)
	Keep in mind that this is a void pointer, which must be cast to the appropriate data type within your callback function.

Returns

SUCCESS	The function was successful.
! = SUCCESS	An error occurred. Refer to Return Codes.

Comments

This callback function gets the available information about the installed TWAIN sources on the system like the names of the TWAIN source, the scanner product family, and the manufacturer.

Required DLLs and Libraries

LTTWN

For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application.

Functions:	L_TwainGetSources.
Topics:	TWAIN Functionality: Callback Functions