Commands by wires (14)

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Then end of the UNIX epoch
http://en.wikipedia.org/wiki/Year_2038_problem Some other notable dates that have passed: $ date -d@1234567890 $ date -d@1000000000

sort lines by length

VMware Server print out the state of all registered Virtual Machines.
I use this command on my machines running VMware Server to print out the state of all registered Virtual machines.

Connect to google talk through ssh by setting your IM client to use the localhost 5432 port
If your firewall or proxy at your location prevents connection to a particular host or port, you can use ssh to tunnel to your home server and do it there instead.

check open ports without netstat or lsof

Create a local compressed tarball from remote host directory
The command uses ssh(1) to get to a remote host, uses tar(1) to archive a remote directory, prints the result to STDOUT, which is piped to gzip(1) to compress to a local file. In other words, we are archiving and compressing a remote directory to our local box.

Batch rename extension of all files in a folder, in the example from .txt to .md
Same thing using bash built-in features instead of a sub-shell.

List out classes in of all htmls in directory
Lists out all classes used in all *.html files in the currect directory. usefull for checking if you have left out any style definitions, or accidentally given a different name than you intended. ( I have an ugly habit of accidentally substituting camelCase instead of using under_scores: i would name soemthing counterBox instead of counter_box) WARNING: assumes you give classnames in between double quotes, and that you apply only one class per element.

Beep siren
Infinitely plays beeps with sinusoidally changing sound frequency. Ideal for alarm on an event.

Create QR codes from a URL.
QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at. Try the following... $ qrurl http://xkcd.com Then open qr.*.png in your favorite image viewer. Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone. URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.


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