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get all Google ipv4 subnets for a iptables firewall for example
a bit shorter, parenthesis not needed but added for clarity

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Random line from bash.org (funny IRC quotes)
bash.org is a collection of funny quotes from IRC. WARNING: some of the quotes contain "adult" jokes... may be embarrassing if your boss sees them... Thanks to Chen for the idea and initial version! This script downloads a page with random quotes, filters the html to retrieve just one liners quotes and outputs the first one. Just barely under the required 255 chars :) Improvment: You can replace the head -1 at the end by: $awk 'length($0)>0 {printf( $0 "\n%%\n" )}' > bash_quotes.txt which will separate the quotes with a "%" and place it in the file. and then: $strfile bash_quotes.txt which will make the file ready for the fortune command and then you can: $fortune bash_quotes.txt which will give you a random quote from those in the downloaded file. I download a file periodically and then use the fortune in .bashrc so I see a funny quote every time I open a terminal.

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"

JSON processing with Python
Validates and pretty-prints the content fetched from the URL.

Suppress output of loud commands you don't want to hear from
This works even if there are spaces in any word in the command line.

Install an mpkg from the command line on OSX
Installing most OSX apps is just a matter of dropping it in /Applications, either GUI-wise or with cp -r. However, many packages are distributed in "mpkg" format, and those have to be installed with an installer. If you don't want to go to the trouble of firing up VNC to install an mpkg, you can use the "installer" command. This will install an application from a .mpkg it to /Applications system-wide. To install a program for just one user, replace "-target /" with "-target username".

Schedule Nice Background Commands That Won't Die on Logout - Alternative to nohup and at
Check out the usage of 'trap', you may not have seen this one much. This command provides a way to schedule commands at certain times by running them after sleep finishes sleeping. In the example 'sleep 2h' sleeps for 2 hours. What is cool about this command is that it uses the 'trap' builtin bash command to remove the SIGHUP trap that normally exits all processes started by the shell upon logout. The 'trap 1' command then restores the normal SIGHUP behaviour. It also uses the 'nice -n 19' command which causes the sleep process to be run with minimal CPU. Further, it runs all the commands within the 2nd parentheses in the background. This is sweet cuz you can fire off as many of these as you want. Very helpful for shell scripts.

Single use vnc-over-ssh connection
This command 1. SSH into a machine 2. Tunnels VNC port to your local computer ("-L 5900:localhost:5900") 3. Runs a single use vnc server ("x11vnc -safer -localhost -nopw -once -display :0") 4. Goes into the background ("-f") 5. Runs VNC viewer on the local computer connecting to the remote machine via the newly created SSH tunnel ("vinagre localhost:5900")

Delicious search with human readable output
You can install filterous with $ sudo apt-get install libxslt1-dev; sudo easy_install -U filterous


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