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prevents replace an existing file by mistake
Use set +o noclobber and you will be able to replace files again

mysql DB size

Generate Random Passwords
If you want a password length longer than 6, changing the -c6 to read -c8 will give you 8 random characters instead of 6. To end up with a line-feed, use this with echo: # echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6` Modern systems need higher strenght, so add some special characters: # < /dev/urandom tr -dc '12345!@#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8

Copy text to the clipboard
Great for little scripts that dig up obscure info that you are going to have to paste into another app anyway.

Using numsum to sum a column of numbers.
numsum is part of of the num-utils package, which is available in some Linux distros and can also be downloaded at http://suso.suso.org/xulu/Num-utils. It contains about 10 different programs for dealing with numbers from the command line. Obviously you can do a lot of things that the num-utils programs do in awk, sed, bash, perl scripts, but num-utils are there so that you don't have to remember the syntax for more complex operations and can just think: compute the sum, average, boundary numbers, etc.

One liner to kill a process when knowing only the port where the process is running
-k (kill option ) . To kill all processes accessing this port

Check availability of Websites based on HTTP_CODE

Display text as though it is being typed out in real time
Pipe Viewer allows you to monitor the progress of a data transfer or command, or to show the time elapsed, among other things. In this use, it limits the transfer rate of the echo command to 10 bytes per second, making your text appear to be typed out in real time as in Hollywood movies. Fun!

Check general system error on AIX
Check general system error on AIX

lotto generator


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