Commands by phatpat (1)

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Echo the latest commands from commandlinefu on the console
Self-referential use of wget.

Random unsigned integer
Reads 4 bytes from the random device and formats them as unsigned integer between 0 and 2^32-1.

a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

function to compute what percentage of X is Y? Where percent/100 = X/Y => percent=100*X/Y
This function make it easy to compute X/Y as a percentage. The name "wpoxiy" is an acronym of "what percentage of X is Y"

Identify long lines in a file
This command displays a list of lines that are longer than 72 characters. I use this command to identify those lines in my scripts and cut them short the way I like it.

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"

Buffer in order to avoir mistakes with redirections that empty your files
A common mistake in Bash is to write command-line where there's command a reading a file and whose result is redirected to that file. It can be easily avoided because of : 1) warnings "-bash: file.txt: cannot overwrite existing file" 2) options (often "-i") that let the command directly modify the file but I like to have that small function that does the trick by waiting for the first command to end before trying to write into the file. Lots of things could probably done in a better way, if you know one...

SSH Copy ed25519 key into your host

Join lines
Even shorter. Stolen from comment posted by eightmillion.

Safely remove old unused kernels in Ubuntu/Debian
Removes piling kernels from /boot, save the current one. This command DOES NOT remove the 'linux-image-generic' package, so you'll continue getting kernel updates


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