Commands by SEJeff (10)

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ssh and attach to a screen in one line.
If you know the benefits of screen, then this might come in handy for you. Instead of ssh'ing into a machine and then running a screen command, this can all be done on one line instead. Just have the person on the machine your ssh'ing into run something like $ screen -S debug Then you would run $ ssh -t user@host screen -x debug and be attached to the same screen session.

list block devices
Shows all block devices in a tree with descruptions of what they are.

Geolocate a given IP address
GeoIP Needs to be installed. Can be done from some distro's or via MaxMind.com for free. There even is a free city database availabble. If the GeoLiteCity is downloaded and installed it will also find more information $ geoiplookup -f /var/lib/GeoIP/GeoLiteCity.dat commandlinefu.com GeoIP City Edition, Rev 1: US, NJ, Absecon, 08201, 39.420898, -74.497704, 504, 609

convert a line to a space

generate 30 x 30 matrix
or $ od /dev/urandom -w60 -An|sed 's/ ..../ /g'|head -n 30 (this one lacks digits 8 and 9)

Get the 10 biggest files/folders for the current direcotry

Set executable permissions on a file under Subversion
This avoids the "chmod +x filename" after performing a check out or export. From http://snipplr.com/view/5277/set-executable-permissions-on-a-file-under-subversion/

Sort IPV4 ip addresses

Remove specific versions of old kernels (Ubuntu/Debian)
If, for example, you want to remove all kernels and headers but the last three versions, you can't use one of that magic all-in-one "remove old stuff" commands. With this simple but elegant command you can remove a range of versions, or a list of versions with e.g. {14,16,20}.

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"


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