Adding
Drivers Within an Application
If you need
your application to implement its own compression routines internally, the
application can add drivers to the ACM by calling the acmDriverAdd function. The application
implements the driver by providing a function that conforms to the acmDriverProc prototype. After the
application has added the driver, the application can use the driver through
the ACM as it would use any other driver.
The ACM
treats drivers as either global or local. An application specifies whether a
driver should be added as global or local when it calls acmDriverAdd.
There are two differences between global and local drivers:
Drivers added as global drivers
are not shared with other applications.
An application can directly
alter the priority of a global driver (but not a local driver) by calling the acmDriverPriority function. The ACM conducts
a prioritized search when seeking an appropriate driver to provide an
implementation of a function call. The ACM always gives local drivers higher
priority than global drivers. The most recently added local driver has highest
priority.