Commands by cfajohnson (19)

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Get the IP address

date offset calculations
The date command does offset calculations nicely, handles concepts like "a month" as you'd expect, and is good for offsets of at least 100M years in either direction.

Convert seconds to human-readable format
This example, for example, produces the output, "Fri Feb 13 15:26:30 EST 2009"

Use xdg-open to avoid hard coding browser commands
I rarely use the system menu to start applications. I use keyboard shortcuts instead. Keyboard shortcuts are convenient time savers. To configure the shortcuts I use gconf-editor or CompizConfig Settings Manager (if I have Compiz turned on). Lately I've been using Chromium as my browser. Since Chromium is under heavy development it occasionally becomes unusable and I have to switch back to Firefox. I was hard-coding the browser command in my keyboard shortcuts. This became problematic with frequent browser hopping. I now use the xdg-open command when defining my keyboard shortcuts. xdg-open opens a file or URL in the user's preferred application. In the metacity keybinging_commands I have xdg-open http://gmail.com where I used to have firefox http://gmail.com. Now when switching browsers I don't have to update each keyboard binding command I just change my default browser in Ubuntu by clicking through the menu: System / Preferences / Preferred Applications / Web Browser. xdg-open is more convenient for this browser hopper.

bulk rename files with sed, one-liner
Renames all files in a directory named foo to bar. foobar1 gets renamed to barbar1 barfoo2 gets renamed to barbar2 fooobarfoo gets renamed to barobarfoo NOTE: Will break for files with spaces AND new lines AND for an empty expansion of the glob '*'

get only time of execution of a command without his output

Remove a range of lines from a file

Remove spaces from filenames - through a whole directory tree.
An example of zsh glob qualifiers.

Another Matrix Style Implementation
A bit different from some of the other submissions. Has bold and uses all c printable characters. Change the bs=value to speed up and increase the sizes of the bold and non-bold strings.

List just the executable files (or directories) in current directory
Does an 'ls' on just the files and directories in the current directory with an execute bit turned on. This version will list directories. Just tack on "-type f" to the start of the find to omit listing directories and list only files.


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