By default, calls to the fflush or _flushall library functions write data to buffers maintained by the operating system. The operating system determines the optimal time to actually write the data to disk. The commit-to-disk feature of the run-time library lets you ensure that critical data is written directly to disk rather than to the operating system's buffers. You can give this capability to an existing program without rewriting it by linking its object files with COMMODE.OBJ.
In the resulting executable file, calls to fflush write the contents of the buffer directly to disk, and calls to _flushall write the contents of all buffers to disk. These two functions are the only ones affected by COMMODE.OBJ.
END Microsoft Specific