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Create a false directory structure for testing your commands
This will make a false directory with the same file names as whatever directory you choose. This is wise to use when testing scripts that alter contents, filenames, or move files. I wrote this after an OOPS I made when renaming a directory of JPGs, PNGs, PSDs that were mixed. I recommend this as I lost over 2000 vacation pictures and some graphics I designed for software and web sites. :( NOTE: This only creates name copies, that data itself is not copied.

generate random password
-B flag = don't include characters that can be confused for other characters (this helps when you give someone their password for the first time so they don't cause a lockout with, for example, denyhosts or fail2ban) -s flag = make a "secure", or hard-to-crack password -y flag = include special characters (not used in the example because so many people hate it -- however I recommend it) "1 10" = output 1 password, make it 10 characters in length For even more secure passwords please use the -y flag to include special characters like so: $ pwgen -Bsy 10 1 output>> }&^Y?.>7Wu

Create sqlite db and store image
Creates a simple sqlite db (img.db) inserts /tmp/Q.jpg on base64 an recorvers it as /tmp/W.jpg

List all symbolic links in current directory
Many competing commands to do this, but since most people want a Long list with Human readable files sizes and want to see All files (including hidden (.*) files) this one wins on simplicity and usefulness. Plus grep is just as, if not more portable than sed or awk, and is more widely understood. :)

Mirror every lvol in vg00 in hp-ux 11.31

It decripts all pgp files in a selection folder and move the output into a file.

Clean the /boot directory
On Fedora clean the boot directory; erase older kernel

List of commands you use most often
Plot your most used commands with gnuplot.

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"

check open ports without netstat or lsof


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