rm -rf versus rm -r: What's the Difference?

• Suppose you have a directory to which you have no apparent permissions:

        $ mkdir -p /tmp/alpha/beta

        $ chmod 0000 /tmp/alpha/beta

        $ ls -l /tmp/alpha/
        total 4
        d--------- 2 jkeenan jkeenan 4096 Jul 20 12:22 beta

• QUIZ: If you call rm -r -- without -f -- what happens?

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