[BusyBox] bug#1292: umount -n option does not work

[Ingo Pakleppa]

Package: busybox
Version 0.60.5 
Severity: normal 

This is either a bug in umount or in the BusyBox.html documentation. The
corresponding -n option in mount works, so I tend to place the bug in
umount.

When I invoke busybox as umount -n /dev/cdrom, I get instead the usage
note: 

Usage: umount [flags] FILESYSTEM|DIRECTORY 

Unount file systems 

Flags: 
  -a Unmount all file systems 
  -r Try to remount devices as read-only if mount is busy 
  -f Force umount (i.e., unreachable NFS server) 
  -l Do not free loop devices (if a loop device has been used) 

Note that the usage note does not include -n, The Busybox documentation
at http://www.busybox.net/downloads/BusyBox.html does include the -n
option and documents it as meaning "don't erase /etc/mtab entries".
Also, mount does have corresponding a working option -n.