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Print random emoji in terminal
This will print a random emoji within the range of 1F600 - 1F64F, which includes all the face emoji. Obviously, this will only show something meaningful if your terminal can display emoji, but it may be useful in scripts. This likely requires recent versions of bash

Compare two CSV files, discarding any repeated lines
The value for the sort command's -k argument is the column in the CSV file to sort on. In this example, it sorts on the second column. You must use some form of the sort command in order for uniq to work properly.

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"

Execute a command with a timeout
A timeout is great, but what if the command is taking longer than expected because it's hung up or ran into some other problem? That's where the -k option comes in. Run "some_command" and timeout after 30s. If the command is still running after 1 minute, it will receive a kill signal.

Download SSL/TLS pem format cert from https web host

Move all comments the top of the file in vim
Python comments begin with a #. Modify to suit other languages. Other uses: Instead of m0 use m$ for end of file or d for deleting all comments.

Print a row of characters across the terminal
Pure Bash This will print a row of characters the width of the screen without using any external executables. In some cases, COLUMNS may not be set. Here is an alternative that uses tput to generate a default if that's the case. And it still avoids using tr. $ printf -v row "%${COLUMNS:-$(tput cols)}s"; echo ${row// /#} The only disadvantage to either one is that they create a variable.

Null a file with sudo

Play 89.3 @TheCurrent and get system notifications on song changes.
Plays the mp3 stream of The Current as a background job. When you are done run: $ fg %1 then to exit Quite possible with Growl for mac I'd guess, although have not tried. Libnotify needed for notification, stream will still work otherwise

create a new script, automatically populating the shebang line, editing the script, and making it executable.
The first argument is the interpreter for your script, the second argument is the name of the script to create.


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