Commands by cardamomo (1)

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Convert all WMF images to SVG recursively ignoring file extension case
This assumes you have the package installed necessary for converting WMF files. On my Ubuntu box, this is libwmf-bin. I used this command, as libwmf is not on my wife's iMac, so I archived the directories containing the WMF files from OS X, ran them on my Ubuntu box, archived the resulting SVGs, and sent them back to her. Quick, simple and to the point. Searches directories recursively looking for extensions ignoring case. This is much more readable and clean than -exec for find. The while loop also gives further flexibility on complex logic. Also, although there is 'wmf2svg --auto', it expects lowercase extensions, and not uppercase. Because I want to ignore case, I need to use the -o option instead. Works in ZSH and BASH. Haven't tested in other shells.

Record live sound in Vorbis (eg for bootlegs or to take audio notes)
This will record the capture channel of your soundcard, directly encoded in Ogg Vorbis, in stereo at quality 5 (I'm using this to record live jam sessions from my line input). You can choose which device to capture (eg. line input, microphone or PCM output) with $ alsamixer -V capture You can do the same thing and live encode in MP3 or FLAC if you wish, just check FLAC and LAME man pages.

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

Force machine to reboot no matter what (even if /sbin/shutdown is hanging)
This will cause your machine to INSTANTLY reboot. No un-mounting of drives or anything. Very handy when something has gone horribly wrong with your server in that co-location facility miles away with no remote hands! Suspect this works with all 2.2, 2.4 and 2.6 Linux kernels compiled with magic-syskey-request support.

Unbelievable Shell Colors, Shading, Backgrounds, Effects for Non-X
I've been using linux for almost a decade and only recently discovered that most terminals like putty, xterm, xfree86, vt100, etc., support hundreds of shades of colors, backgrounds and text/terminal effects. This simply prints out a ton of them, the output is pretty amazing. If you use non-x terminals all the time like I do, it can really be helpful to know how to tweak colors and terminal capabilities. Like: $ echo $'\33[H\33[2J'

Send keypresses to an X application
This is a (last resort) way to automate applications that provide no other ways for automation, it would send 'Hello world' to the currently active window. See the manpage (and the -text and -window entries) for how to send special characters and target specific windows. An example: Using xwininfo, I get the id of my XPlanet background window: [email protected]:19:51:0:~> xwininfo xwininfo: Please select the window about which you would like information by clicking the mouse in that window. xwininfo: Window id: 0x3600001 "Xplanet 1.2.0" Absolute upper-left X: 0 (..etc..) Now I use xvkbd to tell it to close itself: xvkbd -xsendevent -window 0x3600001 -text "Q" Obviously, the best way is to put these commands in a shellscript - just make sure to include a short sleep (sleep .1 should suffice) after each xvkbd call, or some programs will become confused.

Monitor cpu freq and temperature
This is maybe helpfull from system overheat on your linux box

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Get your external IP address with a random command
There's been so many ways submitted to get your external IP address that I decided we all need a command that will just go pick a random one from the list and run it. This gets a list of "Get your external IP" commands from and selects a random one to run. It will run the command and print out which command it used. This is not a serious entry, but it was a learning exercise for me writing it. My personal favourite is "curl". I really don't think we need any other ways to do this, but if more come you can make use of them with this command ;o). Here's a more useful command that always gets the top voted "External IP" command, but it's not so much fun: $ eval $(curl -s|sed -n '/^# Get your external IP address$/{n;p;q}')

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