DTWAIN_StartThread

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The DTWAIN_StartThread function allows an application to call DTWAIN functions in a secondary thread if DTWAIN was initialized in another thread.

LONG DTWAIN_StartThread ( LONG DLLHandle );

Parameters

DLLHandle

The value returned from DTWAIN_SysInitialize or DTWAIN_SysInitializeEx.

Return Values

If the function succeeds, a non-zero value is returned. If the function fails, zero (0) is returned.

Comments

The DTWAIN_StartThread function should be called at the start of a new thread if calls to DTWAIN will be made in the new thread and DTWAIN was initialized in a different thread. Initialization of DTWAIN is done by either calling DTWAIN_SysInitialize of DTWAIN_SysInitializeEx.

The DLLHandle is the return value that DTWAIN_SysInitialize or DTWAIN_SysInitializeEx returned when DTWAIN was initialized.

For example, if DTWAIN_SysInitialize was called in thread 1, and later on, another thread (thread 2) will now make calls to DTWAIN, it is required that the call to DTWAIN_StartThread be made before calling DTWAIN functions in thread 2. The DLLHandle would be the return value of DTWAIN_SysInitialize that was made in thread 1.

Before exiting the thread, a call to DTWAIN_EndThread must be made.

For more information on multithreading issues with DTWAIN, please see DTWAIN Multithreading Issues

TWAIN State Transitions

State 1

Prerequisite Calls

None.

Optional Prerequisite Calls

None.