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Hostname tab-completion for ssh
This is meant for the bash shell. Put this function in your .profile and you'll be able to use tab-completion for sshing any host which is in your known_hosts file. This assumes that your known_hosts file is located at ~/.ssh/known_hosts. The "complete" command should go on a separate line as such: function autoCompleteHostname() { local hosts=($(awk '{print $1}' ~/.ssh/known_hosts | cut -d, -f1)); local cur=${COMP_WORDS[COMP_CWORD]}; COMPREPLY=($(compgen -W '${hosts[@]}' -- $cur )) } complete -F autoCompleteHostname ssh

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

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"

Add Password Protection to a file your editing in vim.
While I love gpg and truecrypt there's some times when you just want to edit a file and not worry about keys or having to deal needing extra software on hand. Thus, you can use vim's encrypted file format. For more info on vim's encrypted files visit: http://www.vim.org/htmldoc/editing.html#encryption

Show a prettified list of nearby wireless APs

Redirect STDIN
Several times, I find myself hitting my up arrow, and changing the search term. Unfortunately, I find myself wasting too much time typing: $ grep kernel /var/log/messages Redirecting STDIN allows me to put the search term at the end so I less cursor movement to change what I'm searching for: $ < /var/log/messages grep kernel If you're using the emacs keyboard binding, then after you press your up arrow, press CTRL+w to erase the word. If this has already been submitted, I couldn't find it with the search utility.

Find the package that installed a command

change dinosaur poop into gold
if firefox is running the database is locked, so you need to copy the places.sqlite file temporarily somewhere to be able to query it...

Run a command, redirecting output to a file, then edit the file with vim.
This is one of those 'nothing' shell functions ...which I use all the time. If the command contains spaces, it must be quoted, e.g. $ vimcmd 'svn diff' /tmp/svndiff.out If I want to keep the output of the command that I'm running, I use vimcmd. If I don't need to keep the output, I use this: $ vim


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