Commands by unixmonkey611 (2)

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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"

Show DeviceMapper names for LVM Volumes (to disambiguate iostat logs, etc)
Emits the device names which will be printed by iostat for an LVM volume; doesn't show the names for the underlying devices when snapshots are being used (the -cow and -real devices in /dev/mapper)

Calculating series with awk: add numbers from 1 to 100
"seq 100" outputs 1,2,..,100, separated by newlines. awk adds them up and displays the sum. "seq 1 2 11" outputs 1,3,..,11. Variations: 1+3+...+(2n-1) = n^2 $ seq 1 2 19 | awk '{sum+=$1} END {print sum}' # displays 100 1/2 + 1/4 + ... = 1 $ seq 10 | awk '{sum+=1/(2**$1)} END {print sum}' # displays 0.999023

Check SSL expiry from commandline

Easily find latex package documentation
If the pdf/dvi/etc documentation for a latex package is already part of your local texmf tree, then texdoc will find and display it for you. If the documentation is not available on your system, it will bring up the package's webpage at CTAN to help you investigate.

Send e-mail if host is 'dead' or not reachable
Cleaner with a mailto assignment in crontab (if the command fails you get an email): MAILTO=admin@example.com 10,30,50 * * * * ping -q -c1 -w3 192.168.0.14 >/dev/null

Purge configuration files of removed packages on debian based systems
also search with aptitude search '~c'

Turns hidden applications transparent in the Mac OS X dock.
In Mac OS X, pressing Command+H will hide an application. While that application's windows vanish, there is no other visual feedback, meaning there is no immediate distinction between an application running with no windows open and a hidden application. This command turns hidden applications' icons transparent, providing a clear and obvious distinction. Change YES to NO to restore the previous functionality.

Check to make sure the whois nameservers match the nameserver records from the nameservers themselves
Change the $domain variable to whichever domain you wish to query. Works with the majority of whois info; for some that won't, you may have to compromise: domain=google.com; for a in $(whois $domain | grep "Domain servers in listed order:" --after 3 | grep -v "Domain servers in listed order:"); do echo ">>> Nameservers for $domain from $a

list all file-types (case-insensitive extensions) including subdirectories


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