Useful bash commands

gistfile1.bat

History: Ctrl + r
Find: find /home/user -name abc.txt
Pipeline: vi `find /home/user -name abc.txt`
Ctrl-x, Ctrl-e will bring up an $EDITOR containing whatever is currently entered into the prompt. (opposed to editing last command actually entered)

Managing remote systems and trying to figure out what hardware you're on and whether it's healthy or not: dmidecode

Repeat last command with "sudo" prepended: sudo !!

Execute <command> with the argument to your previous command: <command> !$ / !* for get all args.

Show all connections with -i: lsof -i (:port_number)
  Only TCP: lsof -iTCP
  For a specific host: lsof [email protected]
  Pointing to a file shows what's interacting with that file: lsof /var/log/messages
  The -p switch lets you see what a given process ID has open, which is good for learning more about unknown processes: lsof -p 10075.
  Using -a allows you to combine search terms
  You can also use the -t with -u to kill everything a user has open: kill -9 `lsof -t -u moviemasher`
  
Pushd pushes a directory onto a stack and switches to it. Popd removes the current directory from the stack and changes to the previous one: pushd/popd

Use it all the time to watch for incoming connections on a certain port: watch -d -n 1 "netstat -an | grep :8080"