Commands by mosaabjm (1)

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Display the standard deviation of a column of numbers with awk
This will calculate a running standard deviation in one pass and should never have the possibility for overflow that can happen with other implementations. I suppose there is a potential for underflow in the corner case where the deltas are small or the values themselves are small.

Skype conversation logs to IRC-format logs

Simulate slow network connection locally
Replace 500ms by the desired delay. To remove it: sudo tc qdisc del dev lo root netem delay 500ms

Grab an interface's IP from ifconfig without screen clutter
Sometimes, you don't really care about all the other information that ifconfig spits at you (however useful it may otherwise be). You just want an IP. This strips out all the crap and gives you exactly what you want.

Search commandlinefu.com from the command line using the API
Search for one/many words on commandlinefu, results in vim for easy copy, manipulation. The -R flag is for readonly mode...you can still write to a file, but vim won't prompt for save on quit. What I'd really like is a way to do this from within vim in a new tab. Something like $ :Tex path/to/file but $ :cmdfu search terms

Show Apt/Dpkg configuration
Shows all configurations to apt and dpkg, rarely changed, you probably still have the default configuration. Go ahead and explore your configuration if you dare, perhaps change your apt-cache directory, Dir::Cache "var/cache/apt/"; or the names of the log files.

Expedient hard disk temprature and load cycle stats
This command is a great way to check to see if acpi is doing damage to your disks by agressivly parking the read arm and wearing down it's life. As you can see, mine has lost half its life. I'm sure this could be shortened though somehow. It will use smartctl to dump the stats and then grep out just the temperature and load cycles for the disk (a load cycle is when a the read arm comes out of park and wears on the drive).

See a full list of compiler defined symbols
From http://lists.debian.org/debian-devel/2001/01/msg00971.html .

Harder, Faster, Stronger SSH clients
We force IPv4, compress the stream, specify the cypher stream to be Blowfish. I suppose you could use aes256-ctr as well for cypher spec. I'm of course leaving out things like master control sessions and such as that may not be available on your shell although that would speed things up as well.

Summary of disk usage, excluding other filesystems, summarised and sorted by size
This command is useful for finding out which directories below the current location use the most space. It is summarised by directory and excludes mounted filesystems. Finally it is sorted by size.


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