FILEOPEN

FILEOPEN_APPEND	Open an existing file for writing and set the position to the end of that file.
FILEOPEN_READ	Open the file for reading.
FILEOPEN_WRITE	Create a new file for writing. Warning: If the file name points to an existing file, it will be overwritten.
FILEOPEN_READWRITE	Open the file for both reading and writing.
FILEOPEN_READ_NOCACHE	Private.
FILEOPEN_SHAREDREAD	Private.
FILEOPEN_SHAREDWRITE	Private.