Commands by azeey

Commands by azeey (4)

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Generate a binary file with all ones (0xff) in it

This is similar to how you would generate a file with all zeros dd if=/dev/zero of=allzeros bs=1024 count=2k
This is sample output - yours may be different.
4

tr '\000' '\377' < /dev/zero | dd of=allones bs=1024 count=2k

azeey · 2009-12-08 16:05:28 4
Alias for getting OpenPGP keys for Launchpad PPAs on Ubuntu

Makes it easy to add keys to new ppa sources entries in apt sources.list Now to add the key for the chromium-daily ppa: launchpadkey 4E5E17B5 Show Sample Output
This is sample output - yours may be different.
```
gpg: requesting key 4E5E17B5 from hkp server keyserver.ubuntu.com
gpg: key 4E5E17B5: "Launchpad PPA for chromium-daily" 2 new signatures
gpg: no ultimately trusted keys found
gpg: Total number processed: 1
gpg:         new signatures: 2
```
9

alias launchpadkey="sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys"

azeey · 2009-06-17 12:02:27 8
Validate and pretty-print JSON expressions.

You can use a site like http://www.jsonlint.com/ or use the command line to validate your long and complex json data. This is part of the simplejson package for python http://undefined.org/python/#simplejson. Wrong json expression example: echo '{ 1.2:3.4}' | python -m simplejson.tool Expecting property name: line 1 column 2 (char 2) Show Sample Output
This is sample output - yours may be different.
```
{
    "json": "obj"
}
```
14

echo '{"json":"obj"}' | python -m simplejson.tool

azeey · 2009-05-10 13:58:05 10
Create several copies of a file

Copy a file to a range of other files. Show Sample Output
This is sample output - yours may be different.
```
test1
test2
test3
test4
test5
```
9

for i in {1..5}; do cp test{,$i};done

azeey · 2009-05-06 21:44:03 5

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Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

Capture video of a linux desktop

This is identical to the original command, but allows you to specify an offset if you have multiple monitors. In this case you'll record a 1366x768 window that's offset by 1366 pixels in the x axis and 0 pixels in the y axis. Note also that the -sameq option has been replaced by -qscale - at least in ffmpeg version 1.2.1 on Fedora 19.

intersection between two files

Place the NUM-th argument of the most recent command on the shell

After executing a command with multiple arguments like cp ./temp/test.sh ~/prog/ifdown.sh you can paste any argument of the previous command to the console, like ls -l ALT+1+. is equivalent to ls -l ./temp/test.sh ALT+0+. stands for command itself ('ls' in this case) Simple ALT+. cycles through last arguments of previous commands.

Start another instance of X via SSH

See udev at work

See how your system works with pendrives/mice/monitors/whatever-you-can-plug-in. Use cases: see on which /dev/... your peripherals are, find out if a specific udev rule is being applied correctly.

Swap a file or dir with quick resotre

This lets you replace a file or directory and quickly revert if something goes wrong. For example, the current version of a website's files are in public_html. Put a new version of the site in public_html~ and execute the command. The names are swapped. If anything goes wrong, execute it again (up arrow or !!).

list files recursively by size

Check a server is up. If it isn't mail me.

This version uses netcat to check a particular service.

Colorize svn stat

Use color escape sequences and sed to colorize the output of svn stat -u. Colors: http://www.faqs.org/docs/abs/HTML/colorizing.html svn stat characters: http://svnbook.red-bean.com/en/1.4/svn-book.html#svn.ref.svn.c.status GNU Extensions for Escapes in Regular Expressions: http://www.gnu.org/software/sed/manual/html_node/Escapes.html

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