The pam_mount project lets you unlock an encrypted filesystem automatically when you log in. The same password used to log in is used as the key to unlock the encrypted filesystem, so you only need to type it once. Using this method, you can easily share a laptop and have only a single user's home directory unlocked and mounted when he logs in. And pam_mount can mount any filesystem, not just encrypted filesystems, so you can use it, for example, with an NFS share that you are interested in but which you might not like to leave mounted when you are not logged in.



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