Commands by zdouglas (1)

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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

Install pip with Proxy
Installs pip packages defining a proxy

Multi-segment file downloading with lftp
This is for files only, for directories 'mirror' has to be used.

Execute a command with a timeout
In this example the command "somecommand" will be executed and sent a SIGALARM signal if it runs for more than 10 seconds. It uses the perl alarm function. It's not 100% accurate on timing, but close enough. I found this really useful when executing scripts and commands that I knew might hang E.g. ones that connect to services that might not be running. Importantly this can be used within a sequential script. The command will not release control until either the command completes or the timeout is hit.

Set Time Zone in Ubuntu
Reconfigures time zone in Ubuntu, which I cannot figure out how to do through the GUI. Worked like a charm to set my time zone to CEST from EDT.

Simple addicting bash game.
Really bored during class so I made this... Basically, you hold period (or whatever) and hit enter after a second and you need to make the next line of periods the same length as the previous line... My record was 5 lines of the same length. It's best if you do it one handed with your pointer on period and ring on enter.

Count number of files in a directory

Cut out a piece of film from a file. Choose an arbitrary length and starting time.
With: -vcodec, you choose what video codec the new file should be encoded with. Run ffmpeg -formats E to list all available video and audio encoders and file formats. copy, you choose the video encoder that just copies the file. -acodec, you choose what audio codec the new file should be encoded with. copy, you choose the audio encoder that just copies the file. -i originalfile, you provide the filename of the original file to ffmpeg -ss 00:01:30, you choose the starting time on the original file in this case 1 min and 30 seconds into the film -t 0:0:20, you choose the length of the new film newfile, you choose the name of the file created. Here is more information of how to use ffmpeg: http://www.ffmpeg.org/ffmpeg-doc.html

Create md5sum of files under the current dir excluding some directories
Useful if you want get all the md5sum of files but you want exclude some directories. If your list of files is short you can make in one command as follow: $ find . -type d \( -name DIR1 -o -name DIR2 \) -prune -o -type f -exec md5sum {} \; Alternatively you can specify a different command to be executed on the resulting files.

Mark packages installed with build-dep for autoremove (on Debian/Ubuntu)
Replace PACKAGE with desired package name. Found here: http://mikebeach.org/2011/04/undo-apt-get-build-dep/


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