unknown option -- ?BusyBox v1.16.1androidBTEP (2010-05-05 21:05:13 PDT) multi-call binary.

Usage: mount [OPTIONS] [-o OPTS] DEVICE NODE

Mount a filesystem. Filesystem autodetection requires /proc.

Options:
	-a		Mount all filesystems in fstab
	-r		Read-only mount
	-w		Read-write mount (default)
	-t FSTYPE	Filesystem type
	-O OPT		Mount only filesystems with option OPT (-a only)
-o OPT:
	loop		Ignored (loop devices are autodetected)
	[a]sync		Writes are [a]synchronous
	[no]atime	Disable/enable updates to inode access times
	[no]diratime	Disable/enable atime updates to directories
	[no]relatime	Disable/enable atime updates relative to modification time
	[no]dev		(Dis)allow use of special device files
	[no]exec	(Dis)allow use of executable files
	[no]suid	(Dis)allow set-user-id-root programs
	[r]shared	Convert [recursively] to a shared subtree
	[r]slave	Convert [recursively] to a slave subtree
	[r]private	Convert [recursively] to a private subtree
	[un]bindable	Make mount point [un]able to be bind mounted
	bind		Bind a file or directory to another location
	move		Relocate an existing mount point
	remount		Remount a mounted filesystem, changing flags
	ro/rw		Same as -r/-w

There are filesystem-specific -o flags.
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