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+molly-guard
+===========
+
+molly-guard attempts to prevent you from accidentally shutting down or
+rebooting remote machines. It does this by injecting a couple of checks before
+the existing commands: halt, reboot, shutdown, and poweroff.
+
+It does this by putting scripts with the same names into /usr/sbin, so it only
+works if you have /usr/sbin before /sbin in your $PATH!
+
+The checks are:
+
+  - test whether the current pty has been created by sshd
+  - test whether a variable $SSH_CONNECTION exists
+
+If any of these tests are successful, molly-guard asks you to type the
+machine's hostname, which should be sufficient to prevent you from doing
+something by accident.
+
+The following situations are still UNGUARDED. If you can think of ways to
+protect against those, please let me know!
+
+  - running sudo within screen or screen within sudo; sudo eats the
+    $SSH_CONNECTION variable, and screen creates a new pty.
+
+  - executing those command in a remote terminal window, that is a XTerm
+    started on a remote machine but displaying on the local X server.
+
+You have been warned. You can use the --molly-guard-do-nothing switch to
+prevent anything from happening, e.g.
+
+  halt --molly-guard-do-nothing
+
+ -- martin f. krafft <madduck@debian.org>  Wed, 12 Mar 2008 20:02:14 +0100