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Convert ascii string to hex
Converts the ascii text to hex from bash. Check the sample output.

intercept stdout/stderr of another process or disowned process
Useful to recover a output(stdout and stderr) "disown"ed or "nohup"ep process of other instance of ssh. With the others options the stdout / stderr is intercepted, but only the first n chars. This way we can recover ALL text of stdout or stderr

Get IPv4 of eth0 for use with scripts
Simple and easy. No regex, no search and replace. Just clean, built-in tools.

Copy a file structure without files
Taken from: http://www.webmasterworld.com/forum40/1310.htm

Copy an element from the previous command
You can specify a range via '-'.

Generate a random password 30 characters long
Find random strings within /dev/urandom. Using grep filter to just Alphanumeric characters, and then print the first 30 and remove all the line feeds.

Performance tip: compress /usr/
Periodically run the one-liner above if/when there are significant changes to the files in /usr/ = Before rebooting, add following to /etc/fstab : = $ /squashed/usr/usr.sfs /squashed/usr/ro squashfs loop,ro 0 0 $ usr /usr aufs udba=reval,br:/squashed/usr/rw:/squashed/usr/ro 0 0 No need to delete original /usr/ ! (unless you don't care about recovery). Also AuFS does not work with XFS

remove empty lines in place with backup
Modify file in place to remove empty lines and create a backup of the original with the extension .bak

Show directories in the PATH, one per line
This version uses Pipes, but is easier for the common user to grasp... instead of using sed or some other more complicated method, it uses the tr command

online MAC address lookup


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