Commands by nulluser (1)

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Preview of a picture in a terminal
This command allows you to see a preview of a picture via the terminal. It can be usefull when you are ssh'ing your server without X-forwarding. To have en example of the output you can get with this command see http://www.vimeo.com/3721117 Download at http://inouire.net/image-couleur.html Sources here: http://inouire.net/archives/image-couleur_source.tar.gz

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

List only directories, one per line
Alternatively, $ ls -F | grep /\$ but will break on directories containing newlines. Or the safe, POSIX sh way (but will miss dotfiles): $ for i in *; do test -d "./$i" && printf "%s\n" "$i"; done

Create a local compressed tarball from remote host directory
This improves on #9892 by compressing the directory on the remote machine so that the amount of data transferred over the network is much smaller. The command uses ssh(1) to get to a remote host, uses tar(1) to archive and compress a remote directory, prints the result to STDOUT, which is written to a local file. In other words, we are archiving and compressing a remote directory to our local box.

Generate random valid mac addresses
Python Alternative

Find commets in jpg files.
Finds comments in jpg files, but I can't figure out how to exclude (in output) files without comments.

Mortality Countdown
watch the seconds of your life tick away - replace YYYY-mm-dd HH:MM:ss w/ your birthtime.

small CPU benchmark with PI, bc and time.
$ # 4 cores with 2500 pi digits $ CPUBENCH 4 2500 $. $ every core will use 100% cpu and you can see how fast they calculate it. $ if you do 50000 digitits and more it can take hours or days

Find the package that installed a command

Efficiently extract lines between markers
GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made. In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start'). My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater.


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