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notify brightness level [custom]
Brightness indicator to be used in scripts that adjust brightness [especially sys that doesn't support automatically]

Block all IP addresses and domains that have attempted brute force SSH login to computer
I use iptables. To rate limit connections. Very easy and no ban lists to manage.

Convert a date to timestamp
Simple way to get a timestamp from a date

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"

for x in `psql -e\l | awk '{print $1}'| egrep -v "(^List|^Name|\-\-\-\-\-|^\()"`; do pg_dump -C $x | gzip > /backups/$x-back.gz
Ran as the postgres user, dumps each database individually. It dumps with the create statements as well, so you can just 'zcat $x-nightly.dmp.gz | psql' to reimport/recreate a database from a backup.

Find 10 largest files in git history

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Find the package that installed a command

Sort files in folders alphabetically
Creates one letter folders in the current directory and moves files with corresponding initial in the folder.

Get the canonical, absolute path given a relative and/or noncanonical path
readlink -f accepts a relative, noncanonical path and emits the corresponding canonical, absolute path.


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