Commands using sleep (289)

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Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

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"

Populate a folder with symbolic links to files listed in an m3u playlist.
This command will place symbolic links to files listed in an m3u playlist into a specified folder. Useful for uploading playlists to Google Music. prefix = The full path prefix to file entries in your .m3u file, if the file paths are relative. For example, if you have "Music/folder/song.mp3" in your list.m3u, you might want to specify "/home/username" as your prefix. list.m3u = Path to the playlist target_folder = Path to the target folder in which you would like to create symlinks

list files recursively by size

Ask for a password, the passwd-style
You can ask repeatedly for a non-blank password using this function: function read_password() { while [ ! -n "$USER_PASSWORD" ]; do read -s -p"Password: " USER_PASSWORD if [ ! -n "$USER_PASSWORD" ]; then echo "ERROR: You must specify a valid password, please try again" fi echo done } Also you can set a time out (in seconds) to write the password read -t 10 -s -p"Password: " USER_PASSWORD_VARIABLE if [ ! $? -eq 0 ]; then echo "Time out!" fi

preserve disk; keep OS clean
if you use disk-based swap then it can defeat the purpose of this function.

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).

move a lot of files over ssh
Useful to move many files (thousands or millions files) over ssh. Faster than scp because this way you save a lot of tcp connection establishments (syn/ack packets). If using a fast lan (I have just tested gigabyte ethernet) it is faster to not compress the data so the command would be: tar -cf - /home/user/test | ssh user@sshServer 'cd /tmp; tar xf -'

Kill google chrome process

LIST FILENAMES OF FILES CREATED TODAY IN CURRENT DIRECTORY
This version eliminates the grep before the awk, which is always good. It works for GNU core utils and ensures that the date output of ls matches the format in the pattern match, regardless of locale, etc. On BSD-based systems, you can easily eliminate both the grep and the awk: find . -maxdepth 1 -Btime -$(date +%kh%lm) -type f


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