Peter's Dance Party

Fear Not

2010-10-01T00:00:00-07:00

Internet is safer when Schneier is at the drums.

Recover Ubuntu encrypted private directory

2010-09-19T00:00:00-07:00

One of my old machines died this past week. Nothing critical on it except for a few documents that were living in my encrypted private directory. The hard drives weren't the point though, so I wasn't too concerned about recovery.

When you first create your encrypted directory, you are given a recovery key. It is recommended that you write this down it keep somewhere safe. I didn't see any point in doing that; either the disk will die and I won't be able to recover anything, or I will be able to use the same mechanism the system uses to get that key.

That key is stored in ~/.ecryptfs/wrapped-passphrase if you only have ~/Private encrypted or /home/.ecryptfs/$USERNAME/.ecryptfs/wrapped-passphrase if you are encrypting your entire home directory. This file is encrypted using your normal login password. You can decrypt it with the command ecryptfs-unwrap-passphrase. That will give you the passphrase needed to mount your private directory: mount -t ecryptfs .Private Private.

Old CS Notes

2010-07-11T00:00:00-07:00

Carry Look-ahead Adder

Binary Integer Division

Next time I need to do binary integer division by hand I'm sure this will be useful. It could also serve as a hilarious interview question.

Lambda Calculus

Emacs variable eval-expression-print-length

2009-04-12T00:00:00-07:00

Often I'll use (pp) or (message) to inspect a data structure in elisp. For example lets say I have a list l:


(setq l '(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15))
(message  l)
 => (1 2 3 4 5 6 7 8 9 10 11 12 ...)

Often times I want to see the entire list instead of the truncated version. That's where eval-expression-print-length comes in. Setting this variable to nil results in the entire list being printed.


(message "%s" eval-expression-print-length)
 => 12
(setq eval-expression-print-length nil)
(message "%s" l)
 => (1 2 3 4 5 6 7 8 9 10 11 12 13 14 15)

Interesting Links for 01-19-2009

2009-01-20T00:00:00-08:00

emacs-oauth
Finally got oauth.el released.

Interesting Links for 01-18-2009

2009-01-19T00:00:00-08:00

My Brightest Diamond, Clare & the Reasons - "Moon River & Ice Ice Baby"
My Brightest Diamond...Amazing

Interesting Links for 01-16-2009

2009-01-17T00:00:00-08:00

Aruba Networks Introduces PCI Compliance Reporting in New AirWave Wireless Management Suite 6.2

Emacs function of the day: (make-indirect-buffer)

2009-01-17T00:00:00-08:00

(make-indirect-buffer base-buffer name &optional clone)


Create and return an indirect buffer for buffer base-buffer, named name.
base-buffer should be a live buffer, or the name of an existing buffer.
name should be a string which is not the name of an existing buffer.
Optional argument clone non-nil means preserve base-buffer's state,
such as major and minor modes, in the indirect buffer.
clone nil means the indirect buffer's state is reset to default values.

Ran across this function today. Occasionally I want to have the same file open to different locations in different frames. You can do this, but when you change buffers in one of those frames, you lose the location of your point. (make-indirect-buffer) solves this problem quite nicely.

Its always fun to learn a new useful emacs function.

Interesting Links for 01-08-2009

2009-01-09T00:00:00-08:00

Richard John Neuhaus, 1936-2009

Interesting Links for 01-07-2009

2009-01-08T00:00:00-08:00

Richard John Neuhaus, 1936-2009
Airwave's New Office Space
Video of our new space before we moved in. Nothing was magnetted to the ceiling when the video was taken.