DTWAIN_SetQueryCapSupport

The DTWAIN_SetQueryCapSupport allows DTWAIN to query capability operations directly from the TWAIN driver.

DTWAIN_BOOL DTWAIN_SetQueryCapSupport ( DTWAIN_BOOL bQuerySources );

Parameters

bQuerySources

   Specifies whether TWAIN Sources will be queried for capability operations.

Return Values

If the function succeeds, TRUE is returned.  If unsuccessful, FALSE is returned.

Comments

DTWAIN_SetQueryCapSupport allows DTWAIN to query the TWAIN Source for all the capability operations possible for each capability defined by the Source.  This function should be called before selecting any Sources.

By default, querying the Source for the capability operations is turned off.  When turned off, DTWAIN will use the capability operations as defined by the TWAIN 1.9 specification for each capability.  Capability operations include getting values, settings values, and resetting values.  For example, the capability DTWAIN_CV_CAPDEVICEONLINE can have the value retrieved, but it cannot be set.

When bQuerySources is TRUE, DTWAIN will query the TWAIN Source for the capability operations.  Therefore, if the Source contains custom capabilities, it is highly recommended that the DTWAIN_SetQueryCapSupport be called, since DTWAIN has no information on its own concerning custom capability operations.  Please see more information on this in the Information on Custom Capabilities section.