Commands by vayn (1)

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Monitor a file's size
use "watch" instead of while-loops in these simple cases

Find all directories on filesystem containing more than 99MB
Finds all directories containing more than 99MB of files, and prints them in human readable format. The directories sizes do not include their subdirectories, so it is very useful for finding any single directory with a lot of large files.

command line fu roulette
retrieves the html from a random command line fu page, then finds commands on the page and prints them alternatively, pipe to bash (add "| bash" to the end) to execute the command (very risky) edit: had to adjust to properly display the portion that replaces HTML characters (e.g. " -> ")

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"

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"

Stripping ^M at end of each line for files

Open Remote Desktop (RDP) from command line and connect local resources
The above command will open a Remote Desktop connection from command line, authenticate using default username and password (great for virtual machines; in the exampe above it's administrator:password), create a shared folder between your machine and the other machine and configure resolution to best fit your desktop (I don't like full screen because it make the desktop panels to disappear). The command will run in the background, and expect to receive parameters. You should enter hostname or IP address as a parameter to the command, and can also override the defaults parameters with your own.

Install pip with Proxy
Installs pip packages defining a proxy

Synchronize both your system clock and hardware clock and calculate/adjust time drift
Do not run this command if you already have ntpd running! This needs to run as root, for example with sudo: $ sudo ntpdate pool.ntp.org && sudo hwclock --systohc && sudo hwclock --adjust This command will fetch accurate time from NTP servers and synchronize your system clock, then it will use the system clock to synchronize your hardware clock, and will calculate the time drift.

FizzBuzz in one line of Bash
The (in)famous "FizzBuzz" programming challenge, answered in a single line of Bash code. The "|column" part at the end merely formats the output a bit, so if "column" is not installed on your machine you can simply omit that part. Without "|column", the solution only uses 75 characters. The version below is expanded to multiple lines, with comments added. for i in {1..100} # Use i to loop from "1" to "100", inclusive. do ((i % 3)) && # If i is not divisible by 3... x= || # ...blank out x (yes, "x= " does that). Otherwise,... x=Fizz # ...set x to the string "Fizz". ((i % 5)) || # If i is not divisible by 5, skip (there's no "&&")... x+=Buzz # ...Otherwise, append (not set) the string "Buzz" to x. echo ${x:-$i} # Print x unless it is blanked out. Otherwise, print i. done | column # Wrap output into columns (not part of the test).

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