Assuming that 219,229 and 221 are entries in history, I recall them in a single line for execute multiple commands

219 ifdown wlan0

...

221 ifup wlan0

...

229 iwconfig wlan0 mode Managed

so the result is execution of # ifdown wlan0 ; iwconfig wlan0 mode Managed ; ifup wlan0

tailf same as tail -f follow the flow of a log file, showing it in real time to stdout.

Yeah, there are many ways to do that.

Doing with sed by using a for loop is my favourite, because these are two basic things in all *nix environments. Sed by default does not allow to save the output in the same files so we'll use mv to do that in batch along with the sed.

When you have to manage lot of servers, it's boring to type ssh root@myhost for each connection. Now you can type juste "s someting" and you are connected.

You can too add bash_completion script to complet with tab the name of your servers. This will be the next tips from me ;)

You will need libnotify-bin for this to work:

From time to time one forgets either thier gpg key or other passphrases. This can be very problematic in most cases. But luckily there's this script. Its based off of pwsafe which is a unix commandline program that manages encrypted password databases. For more info on pwsafe visit, http://nsd.dyndns.org/pwsafe/.

What this script does is it will help you store all your passphrases for later on and allow you to copy it to your clipboard so you can just paste it in, all with one password. Pretty neat no?

You can find future releases of this and many more scripts at The Teachings of Master Denzuko - denzuko.wordpress.com.

With this command you can use shell variables inside sed scripts.

This is useful if the script MUST remain in an external file, otherwise you can simply use an inline -e argument to sed.

bash.org is a collection of funny quotes from IRC.

WARNING: some of the quotes contain "adult" jokes... may be embarrassing if your boss sees them...

Thanks to Chen for the idea and initial version!

This script downloads a page with random quotes, filters the html to retrieve just one liners quotes and outputs the first one.

Just barely under the required 255 chars :)

Improvment:

You can replace the head -1 at the end by:

which will separate the quotes with a "%" and place it in the file.

and then:

which will make the file ready for the fortune command

and then you can:

which will give you a random quote from those in the downloaded file.

I download a file periodically and then use the fortune in .bashrc so I see a funny quote every time I open a terminal.

See all fonts installed in your system

This is a bit to bit copy so if you have a 500GB hard disk it will take a long time even if have Gigabit Ethernet

This opens up nautilus in the current directory, which is useful for some quick file management that isn't efficiently done from a terminal.

Find all corrupted jpeg in the current directory, find a file with the same name in a source directory hierarchy and copy it over the corrupted jpeg file.

Convenient to run on a large bunch of jpeg files copied from an unsure medium.

Needs the jpeginfo tool, found in the jpeginfo package (on debian at least).

Copy a file to a range of other files.

I have a bash alias for this command line and find it useful for searching C code for error messages.

The -H tells grep to print the filename. you can omit the -i to match the case exactly or keep the -i for case-insensitive matching.

This find command find all .c and .h files

Aureport is a tool for displaying auditd system log. -x options cause to display launched executable on system.

Aureport work with auditd so auditd must be installed an running on a system.

Tested on CentOS / Debian

Please take notice that if you are going to use an JPG file for shadow effect,

let change -background none to -background white!

Because -background none make a transparent effect while JPG doesn't support transparent! And when viewing, you will get a bacl box!

So we will use an white background under! We can use other color as well!

The colors are defined as variables.

e.g.

RED="\[\033[01;31m\]"

BLUE="\[\033[01;34m\]"

Runs an instance of screen with name of "name_me" and command of "echo "hi""

To reconnect to screen instance later use:

screen -r name_me

While I love gpg and truecrypt there's some times when you just want to edit a file and not worry about keys or having to deal needing extra software on hand. Thus, you can use vim's encrypted file format.

For more info on vim's encrypted files visit: http://www.vim.org/htmldoc/editing.html#encryption