BusyBox v1.10.2 (Debian 3:1.10.2.legal-1osso30+0m5) built-in shell (ash)
Enter 'help' for a list of built-in commands.

Nokia-N900:~# rm -r /and
Nokia-N900:~# df -h/
df: invalid option -- /
BusyBox v1.10.2 (Debian 3:1.10.2.legal-1osso30+0m5) multi-call binary

Usage: df [-hmk] [FILESYSTEM...]


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is that helped me ?