Commands tagged pipes (12)

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Find the package that installed a command
Put this one-line function somewhere in your shell init, re-login and try $ whatinstalled This is an elaborate wrapper around "dpkg -S", with numerous safeguards. Symlinks and command aliases are resolved. If the searched command is not an existing executable file or was installed by some other means than dpkg/apt, nothing is printed to stdout, otherwise the package name.

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"

Start screen in detached mode
Start screen in detached mode, i.e., already running on background. The command is optional, but what is the purpose on start a blank screen process that way? It's useful when invoking from a script (I manage to run many wget downloads in parallel, for example).

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

'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"

Shrink more than one blank lines to one in VIM.

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"

Sort dotted quads
Sort a list of IPV4 addresses in numerical order. Great as a filter, or within vim using !}

Install pip with Proxy
Installs pip packages defining a proxy

Remove all unused kernels with apt-get
Remove old kernels (*-generic and *-generic-pae) via apt-get on debian/ubuntu based systems. Tested on ubuntu 10.04 - 12.04.


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