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IFS - use entire lines in your for cycles
When you use a "for" construct, it cycles on every word. If you want to cycle on a line-by-line basis (and, well, you can't use xargs -n1 :D), you can set the IFS variable to .

Working random fact generator
Though without infinite time and knowledge of how the site will be designed in the future this may stop working, it still will serve as a simple straight forward starting point. This uses the observation that the only item marked as strong on the page is the single logical line that includes the italicized fact. If future revisions of the page show failure, or intermittent failure, one may simply alter the above to read. $ wget randomfunfacts.com -O - 2>/dev/null | tee lastfact | grep \ | sed "s;^.*\(.*\).*$;\1;" The file lastfact, can then be examined whenever the command fails.

runs a bash script in debugging mode

Displays process tree of all running processes
G - uses VT100 line drawing a - shows command line arguments of process p - prints PID of process For other options, man pstree :)

'micro' ps aux (by mem/cpu)
mac os x: ps aux | awk '{print($1" "$3" "$4" "$11);}' | grep -v "0,0" linux: ps aux | awk '{print($1" "$3" "$4" "$11);}' | grep -v "0.0"

Set blanket packet/second limit on network interface for Ubuntu VPS server
VPS server hosts suspect DOS attack if PPS is too high. This limits packets at the interface level. Do "sudo apt-get install iptables-persistent" to make persistent, or, if you already have, reconfigure with "sudo dpkg-reconfigure iptables-persistent"

Extract a bash function
I often need to extract a function from a bash script and this command will do it.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Copy structure
Clone directory structure without the files

Get ssh server fingerprints
Get your server's fingerprints to give to users to verify when they ssh in. Publickey locations may vary by distro. Fingerprints should be provided out-of-band.


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