Returns an errno, a file handle (optional).
-No creation, or trunctation flags (O_CREAT, O_EXCL, O_TRUNC) will be passed to open().
+No creation, or truncation flags (O_CREAT, O_EXCL, O_TRUNC) will be passed to open().
The fileinfo hash reference contains flags from the Fuse open call which may be modified by the module. The only fields presently supported are:
direct_io (version 2.4 onwards)
keep_cache (version 2.4 onwards)