Determining Available Disk Space
Memory is usually at a premium on a Windows CE–based device. Use the GetDiskFreeSpaceEx function to retrieve information about a file system partition, including total bytes and free bytes available. GetDiskFreeSpaceEx works on any file system, including installed file systems. You can use the GetStoreInformation function also to determine the current size of the object store, and how much free memory is available in the object store.