This is a command you see mentioned alot by Gentoo monkeys.

They say to use it after every update of GCC, any library you might use and glibc.

They argue that compiling and recompiling everything like this will optimize the system alot more because you are recompiling the entire system (gcc, glibc etc) with nativly compiled versions of themselves. Same goes for all libraries etc.

I doubt the difference in working speed is really worth the hours and hours you end up having your computer compile the same stuff again and again though.

On Debian systems, choose which command provides java. Works for all alternatives listed in /etc/alternatives.

First you need to instal aircrack-ng

Use this command if you need to put your wireless card into monitor mode.

interface = wlan0 || wifi0 || ath0 et ceatera...

channel = 6, 11, 10, 9 et ceatera

This is a little bash script that will take all files following the *gz pattern in the directory and apply the tar -zxvf command to them.

Have you ever had to scp a file to your work machine in order to copy its contents to a mail? xclip can help you with that. It copies its stdin to the X11 buffer, so all you have to do is middle-click to paste the content of that looong file :)

This is useful when you want to copy a file and also force a user, a group and a mode for that file.

Note: if you want to move that file instead of copying it, you can use

which will remove the file only if the install command went fine.

Where < target > may be a single IP, a hostname or a subnet

-sS TCP SYN scanning (also known as half-open, or stealth scanning)

-P0 option allows you to switch off ICMP pings.

-sV option enables version detection

-O flag attempt to identify the remote operating system

Other option:

-A option enables both OS fingerprinting and version detection

-v use -v twice for more verbosity.

I use this all the time for taking manual backups of stuff i want to keep but not important enough to backup regularly.

You can convert a FAT or FAT32 volume to an NTFS volume without formatting the drive, though it is still a good idea to back up your data before you convert.

This is a useful command that gives the hostname and the IP Address of your machine, on many OS. Tested on Linux and Solaris.

host command here is followed by `hostname`. Note the ` in the command is a back quote (or grave accent or back tic that usually shares the space with the ~ key). No other options are specified. See sample output.

This command lets you view the cam on remote machine whilst connected via ssh. Note: must connect to remote machine with ssh -Y.

Nice for ie6 for linux

This command deletes all files in all subfolders if their name or path contains "deleteme".

To dry-run the command without actually deleting files run:

Sends the microphone input from PC1 to the speakers of PC2. Do the same in reverse to have an actual conversation ;) ... maybe with another port tough

I know there are a lot of random password generators out there, but I wanted something that put out something besides hex. Set count equal to the number of bytes you want.

Dashboard is OS X utility application. When you hit F12, Dashboard springs forward, dimming the background, some people have claimed memory or performance problems. In my case, I just don't use it, there may be other reasons you?d rather not have Dashboard available.

Change YES to NO to restore the previous functionality.

In Mac OS 9, the "New Folder" keyboard shortcut was Command+N, but in Mac OS X this was changed to "New Finder Window" instead, with "New Folder" taking the more awkward shortcut of Command+Shift+N. This command reverses their mappings.

Mac OS X 10.5 (Leopard) introduced a new, 3D, reflective Dock. For those of us who prefer the Dock to be a little less distracting, this command is the answer. The Dock will be rendered in the same style as when pinned to the left- or right-hand side of the screen. Replace YES with NO to restore the 3D Dock.

If you need to delete all redundant ".svn" directories from a given path and all its subdirectories, use this command !

Particulary useful if you want to upload to an ftp server, but don't use svn or if you need to update/backup some source code to another directory.

You can also try "svn export . /new/path/without/svn/dirs" (also from the CLI)

-p parameter tells wget to include all files, including images.

-e robots=off you don't want wget to obey by the robots.txt file

-U mozilla as your browsers identity.

--random-wait to let wget chose a random number of seconds to wait, avoid get into black list.

Other Useful wget Parameters:

--limit-rate=20k limits the rate at which it downloads files.

-b continues wget after logging out.

-o $HOME/wget_log.txt logs the output