I've corrected the function. My octal conversion formula was completely wrong. Thanks to pgas at http://mywiki.wooledge.org/BashFAQ/071 for setting me straight. The new function is from pgas and is very fast.

Using column to format a directory listing

change the *.avi to whatever you want to match, you can remove it altogether if you want to check all files.

emulates bash4's "echo {03..20}"

Uses bash3 builtin function printf

Rainbow, instead of greys

it is not work with Cygwin's bash3.X. Test in Linux.

use printf "%'f" number while it is floating point number

I use this as an alias:

alias authplain "printf '\!:1\0\!:1\0\!:2' | mmencode | tr -d '\n' | sed 's/^/AUTH PLAIN /'"

then..

# authplain someuser@somedomain.com secretpassword

AUTH PLAIN c29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac29tZXVzZXJAc29tZWRvbWFpbi5jb20Ac2VjcmV0cGFzc3dvcmQ=

#

awk can clear the screen while displaying output. This is a handy way of seeing how many lines a tail -f has hit or see how many files find has found. On solaris, you may have to use 'nawk' and your machine needs 'tput'

Seen here: http://www.pixelbeat.org/docs/terminal_colours/

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.

This command adds the numbers 10, 12, 14 to a bunch of mp3's in the current working directory. You can then run the command replacing the inital i=10 with i=11 to add 11,13,15 in another directory then mv the files together and the first files interweave with the second group of files. I used this to weave a backlog of a podcast with other podcast so I didn't get sick of one while I was catching up. I started at 10 because printf blows up with 0 padded numbers 08 and 09 which kind of makes the printf command redundant as it was used to pad numbers 1 - 9 so they would come first and not get sorted incorrectly

Displays six rows and five columns of random numbers between 0 and 1. If you need only one column, you can dispense with the "for" loop.

Show the number of failed tries of login per account. If the user does not exist it is marked with *.

works the same as R's t()

Old snapshots can cause problems. It's best to remove them when finished. I use this script to remove all snapshots. The "while read" command is necessary because my vm names contain spaces. The "time" command reports how long the process runs.

Sometimes, in a shell script, you need a random number bigger than the range of $RANDOM. This will print a random number made of four hex values extracted from /dev/urandom.

Check if Fail2Ban is running on the system and alert it with a message in the terminal

just for fun