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Kill all processes that listen to ports begin with 50 (50, 50x, 50xxx,...)
Run netstat as root (via sudo) to get the ID of the process listening on the desired socket. Use awk to 1) match the entry that is the listening socket, 2) matching the exact port (bounded by leading colon and end of column), 3) remove the trailing slash and process name from the last column, and finally 4) use the system(…) command to call kill to terminate the process. Two direct commands, netstat & awk, and one forked call to kill. This does kill the specific port instead of any port that starts with 50. I consider this to be safer.

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"

Determining the excat memory usages by certain PID
this command gives you the total number of memory usuage and open files by the perticuler PID.

get you public ip address
Relies on ifconfig.me functioning. It's about as easy as it gets, and memorable to old geeks too.

Convert current symbolic directory into physical directory

Show the command line for a PID, converting nulls to spaces and a newline

Encode a string using ROT47
This command will encode a string using the ROT47 cipher.

See n most used commands in your bash history
You can append these commands to the bottom of the history file to access them easier with the Up key: $ sort ~/.bash_history|uniq -c|sort -n|tail -n 10|tr -s " "|cut -d' ' -f3- >> ~/.bash_history

Print a cron formatted time for 2 minutes in the future (for crontab testing)
Another function to stick into your .bashrc This spits out the time two minutes in the future, but already formatted for pasting into your crontab file for testing without any thought required on your part. Frequently things don't work the way you expect inside a crontab job, and you probably want to find out now that your $PATH is completely different inside of cron or other global variables aren't defined. So this will generate a date you can use for testing now, and then later you can change it to run at 5:37 am on a Sunday evening.

Show permissions of current directory and all directories upwards to /
NB not 'namei -m .', as it slices the path you give it.


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