Commands by arighi (1)

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Shrink more than one blank lines to one in VIM.

Print only the odd lines of a file
NR%2 == 1 on odd lines and 0 on even lines

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

Debug how files are being accessed by a process
Instead of looking through `lsof` results, use inotifywait!

Print a row of characters across the terminal
Print a row of characters across the terminal. Uses tput to establish the current terminal width, and generates a line of characters just long enough to cross it. In the example '#' is used. It's possible to use a repeating sequence by dividing the columns by the number of characters in the sequence like this: $ seq -s'~-' 0 $(( $(tput cols) /2 )) | tr -d '[:digit:]' or $ seq -s'-~?' 0 $(( $(tput cols) /3 )) | tr -d '[:digit:]' You will lose chararacters at the end if the length isn't cleanly divisible.

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"

Show a Command's Short Description
The whatis command displays a short description for the command you list on the command line. It is useful to quickly learn what a command does

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 Note also that the -sameq option has been replaced by -qscale - at least in ffmpeg version 1.2.1 on Fedora 19.

Lists all listening ports together with the PID of the associated process
This command is more portable than it's cousin netstat. It works well on all the BSDs, GNU/Linux, AIX and Mac OS X. You won't find lsof by default on Solaris or HPUX by default, but packages exist around the web for installation, if needed, and the command works as shown. This is the most portable command I can find that lists listening ports and their associated pid.

Substitute audio track of video file using mencoder
Creates a new video file with video stream copied from input file and a different audio stream

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