This function checks whether a region of memory is valid with respect to the caller process.
Note This function is no longer supported as of CE 6.0.
MapCallerPtr is generally used in device driver I/O controls to validate the pointer parameters passed by the caller process. Because device drivers usually run with higher privileges and have access to more memory, if you do not call this function to validate the parameters, it could overwrite a process's memory. It could also overwrite the kernel memory if called from a malicious application.