FCB is a fast replacement for Windows FC.EXE. It supports only the binary mode of the original
The original acts often very dull: Comparing large files it allocates nearly all the free memory. And it reads the files thru the Windows file cache even if its useless because of the file size.
FCB reads directly from the disk. It uses three separate threads for reading the two files and for comparing. So FCB is nearly always faster than FC.EXE. The only exeption is when you compare a file with itself. FCB then really reads the data twice from disk while FC gets the data of the second file from the Windows file cache.
The usage is similar to the original but the /B parameter doesn't exist because FCB only supports the binary mode, processing sub-dirs isn't implemented yet.
FCB FileSpec1 FileSpec2