Commands by leonardovaz (2)

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Script executes itself on another host with one ssh command
Now put more interesting stuff on the script in replacement of hostname, even entire functions, etc, and stuff. hosta> cat myScript.sh #!/bin/sh [ $1 == "client" ] && hostname || cat $0 | ssh $1 /bin/sh -s client hosta> myScript.sh hostb hostb hosta>

Tricky implementation of two-dimensional array in Bash.
Since Bash doesn't support two-dimensional arrays, you can limit your columns length by some big enough constant value ( in this example 100 ) and then index the array with i and j, or maybe write your own get() and set() methods to index the array properly like I implemented for example ( see Sample output ). For example for i=0 and j=0...99 you'll pick up one of 100 elements in the range [0,99] in the one-dimensional array. For i=1 and j=0...99 you'll pick up one of 100 elements in the range [100,199]. And so on. Be careful when using this, and remember that in fact you are always using one-dimensional array.

Get the absolute path of a file

Change user within ssh session retaining the current MIT cookie for X-forwarding
When you remotely log in like "ssh -X userA:host" and become a different user with "su UserB", X-forwarding will not work anymore since /home/UserB/.Xauthority does not exist. This will use UserA's information stored in .Xauthority for UserB to enable X-forwarding. Watch http://prefetch.net/blog/index.php/2008/04/05/respect-my-xauthority/ for details.

ASCII webcam live stream video using mplayer
Mplayer starts a webcam capture using ASCII art. Only mplayer required

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"

pinky - user info
Gives information about user's home directory and real name and shell user is having.

kill all processes using a directory/file/etc
This command will kill all processes using a directory. It's quick and dirty. One may also use a -9 with kill in case regular kill doesn't work. This is useful if one needs to umount a directory.

nmap fast scan all ports target

Regex to remove HTML-Tags from a file
This regular expression removes all HTML-Tags from the file.


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