Commands by weidenrinde (1)

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Default value or argument
I used it for this function, which prints hashes: function liner { num_lines=${1:-42} echo printf %${num_lines}s|tr " " "#" echo } Note the colon-dash, instead of the usual colon-equals.

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).

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.

This will take the last two commands from bash_history and open your editor with the commands on separated lines

Get International Space Station sighting information for your city
This command outputs a table of sighting opportunities for the International Space Station. Find the URL for your city here: http://spaceflight.nasa.gov/realdata/sightings/

Watch active calls on an Asterisk PBX

Generate binary sequence data

Delete files older than..
This command will delete files i a given path (/dir_name) , which older than given time in days (-mtime +5 will delete files older than five days.

Check if a domain is available and get the answer in just one line
Returns nothing if the domain exists and 'No match for domain.com' otherwise.

Read the output of a command into the buffer in vim
This will append the output of "command" to whatever file you're currently editing in vim. Who else has good vim tricks? :)


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