Commands by seattlegaucho (3)

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Generate MD5 of string and output only the hash checksum

Pretty Print a simple csv in the command line
Will handle pretty much all types of CSV Files. The ^M character is typed on the command line using Ctrl-V Ctrl-M and can be replaced with any character that does not appear inside the CSV. Tips for simpler CSV files: * If newlines are not placed within a csv cell then you can replace `map(repr, r)` with r

diff will usually only take one file from STDIN. This is a method to take the result of two streams and compare with diff. The example I use to compare two iTunes libraries but it is generally applicable.
diff is designed to compare two files. You can also compare directories. In this form, bash uses 'process substitution' in place of a file as an input to diff. Each input to diff can be filtered as you choose. I use find and egrep to select the files to compare.

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"

Port scan a range of hosts with Netcat.
Simple one-liner for scanning a range of hosts, you can also scan a range of ports with Netcat by ex.: nc -v -n -z -w 1 192.168.0.1 21-443 Useful when Nmap is not available:) Range declaration like X..X "for i in {21..29}" is only works with bash 3.0+

Displays the attempted user name, ip address, and time of SSH failed logins on Debian machines
A variation of a script I found on this site and then slimmed down to just use awk. It displays all users who have attempted to login to the box and failed using SSH. Pipe it to the sort command to see which usernames have the most failed logins.

Convert from a decimal number to a binary number

Get information about memory modules
To take information about the characteristics of the installed memory modules.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

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.


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