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Bash alias for creating screen session containing IRSSI, named irssi, while checking if existing session is created
Bash alias for easy irssi within screen, attempts to attach to existing irssi session, if one exists, otherwise creates one - Including wipe for when system reboots and leaves "dead" session.

Create a 5 MB blank file via a seek hole
Similar to the original, but is much faster since it only needs to write the last byte as zero. A diff on testfile and testfile.seek will return that they are the same.

Send e-mail if host is 'dead' or not reachable
Cleaner with a mailto assignment in crontab (if the command fails you get an email): MAILTO=admin@example.com 10,30,50 * * * * ping -q -c1 -w3 192.168.0.14 >/dev/null

How to backup hard disk timely?
'data' is the directory to backup, 'backup' is directory to store snapshots. Backup files on a regular basis using hard links. Very efficient, quick. Backup data is directly available. Same as explained here : http://blog.interlinked.org/tutorials/rsync_time_machine.html in one line. Using du to check the size of your backups, the first backup counts for all the space, and other backups only files that have changed.

Install pip with Proxy
Installs pip packages defining a proxy

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Convert images to a multi-page pdf
The linux package imagmagick is required for this command

Mnemonic for `nice` and `renice` command
This is just a phrase I use to help me remember which way is what when using nice (top, renice, etc.), and not a command, (unless you really want this in your .bash_history to help remind you.) I was using the command `man nice ` way too much just to look up which way is what. This saves 9 keystrokes every time I remember it. Make sure you downvote me if you think mnemonics sux. Otherwise I hope this helps someone else.

Export MySQL tables that begin with a string

Create a bunch of dummy text files
Using the 'time' command, running this with 'tr' took 28 seconds (and change) each time but using base64 only took 8 seconds (and change). If the file doesn't have to be viewable, pulling straight from urandom with head only took 6 seconds (and change)


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