1d2e5d50a4
This doesn't add FLV file output to the user interface yet, but we'll get around to that eventually. This just adds an FLV output type. Also, removed ftello/fseeko because off_t is a really annoying data type, and I'd rather have a firm int64_t for large sizes, so I named it to os_fseeki64 and os_ftelli64 instead, and changed the file size function to return an int64_t.