Commands by vinayakgadkari (1)

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Which files/dirs waste my disk space
I added -S to du so that you don't include /foo/bar/baz.iso in /foo, and change sorts -n to -h so that it can properly sort the human readable sizes.

Bash prompt with user name, host, history number, current dir and just a touch of color
I put that line in my .bash_profile (OS X) and .bashrc (Linux). Here is a summary of what the \char means: n=new line, u=user name, h=host, !=history number, w=current work directory The \[\e[32m\] sequence set the text to bright green and \[\e[0m\] returns to normal color. For more information on what you can set in your bash prompt, google 'bash prompt'

Join the content of a bash array with commas
$ DOCKER_APP_VARS=(DATABASE_USER=dbuserro, DATABASE_PASSWORD=maipass) [jeff@omniscience container] (master)$ echo docker run $(printf -- " -e %s" ${DOCKER_APP_VARS[*]}) -name 12factorapp mattdm/fedora-small docker run -e DATABASE_USER=dbuserro, -e DATABASE_PASSWORD=maipass -name 12factorapp mattdm/fedora-small Note that the printf method by itsself doesn't include a newline (\n), so you'll need to embed it into an echo statement or something that does.

Reload all sysctl variables without reboot
Use `sysctl -p` without argument will only load /etc/sysctl.conf, but user configs always put in /etc/sysctl.d/*.conf, `sysctl --system` will load all the config files

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"

get ip of all running docker containers
pretty self explanitory

Copy your ssh public key to a server from a machine that doesn't have ssh-copy-id
If you use Mac OS X or some other *nix variant that doesn't come with ssh-copy-id, this one-liner will allow you to add your public key to a remote machine so you can subsequently ssh to that machine without a password.

For finding out if something is listening on a port and if so what the daemon is.

Multi line grep using sed and specifying open/close tags
This line does not include your closing tag in the output.

See system users

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