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Delete leading whitespace from the start of each line

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

Make a server's console beep when the network is down
This is like ping -a, but it does the opposite. It alerts you if the network is down, not up. Note that the beep will be from the speaker on the server, not from your terminal. Once a second, this script checks if the Internet is accessible and beeps if it is not. I define the Net as being "UP", if I can ping Google's public DNS server (8.8.8.8), but of course you could pick a different static IP address. I redirect the beep to /dev/console so that I can run this in the background from /etc/rc.local. Of course, doing that requires that the script is run by a UID or GID that has write permissions to /dev/console (usually only root). Question: I am not sure if the -W1 flag works under BSD. I have only tested this under GNU/Linux using ping from iputils. If anybody knows how portable -W is, please post a comment.

Check if running in an X session
If you want to display a dialog (using xdialog/kdialog/zenity) you need to make sure that you have a valid X session. Checks for the existence of the DISPLAY variable.

cloning partition tables under Solaris

Remove multiple same rpm packages
If somehow if you get more than 1 same name rpm package install, then it cannot be removed by using simple rpm -e as it gives you more than one rpm matches error. The --matches will help to remove all the same name rpm packages.

Plot frequency distribution of words from files on a terminal.
Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files.

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"

geoip information
Show external IP and geolocation information. Primary feature is the use of tee to echo IP _and_ send to geoiplookup command...Use IP as input for as many commands as you want with more >( [command] ) Thanks to http://www.commandlinefu.com/commands/view/6334/ Requires MaxMind DB and geoiplookup tool. Sample output has IP obfuscated on first line, lines 2-4 from having MaxMind Country && MaxMind City DBs installed

Create a square thumbnail or favicon using ImageMagick
Resize `file.png` to a 32x32 px image. Use a value other than 32 to create other icon sizes (e.g. 16x16 or 32x32). Combine two favicon sizes using: `convert icon-16px.png icon-32px.png favicon.ico` For a social media preview image, use `2:1#` for the extent and `1200` for the scale.


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