Using CFS, the Cryptographic Filesystem
Briefly, CFS allows you to safeguard your files in encrypted form in a normal directory. By using a key (or password, if you will), you temporarily decrypt your files to clear-text form for the window of time in which you need to work with them.
CFS makes your clear-text files available to you via a local loopback NFS mount; the CFS documentation refers to this as an "attach". Modifications you make to your clear-text files then are reflected automatically in the encrypted versions. You end your CFS session with a "detach", which makes your clear-text files disappear until the next time that you attach them.
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