Commands by octopus (9)

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Bash scripts encryption and passphrase-protection
This function will encrypt a bash script and will only execute it after providing the passphrase. Requires mcrypt to be installed on the system.

ssh autocomplete based on ~/.ssh/config
I use this in my bashrc to expand hosts defined in ~/.ssh/config: function _ssh_completion() { perl -ne 'print "$1 " if /^Host (.+)$/' ~/.ssh/config } complete -W "$(_ssh_completion)" ssh Here's a great article on how to setup your own ~/.ssh/config: http://blogs.perl.org/users/smylers/2011/08/ssh-productivity-tips.html

Turn shell tracing and verbosity (set -xv) on/off with 1 command!
Turn shell tracing and verbosity (set -xv) on/off in any Bourne-type shell If either -x or -v is set, the function turns them both off. If neither is on, both are turned on.

parrallel execution of a command on remote hosts by ssh or rsh or ...
parrallel execution of a command on remote host by ssh or rsh or ... very useful for cluster management (software update)

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"

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" }

Select rectangular screen area
Hold 'Ctrl' + 'Alt' key while selecting rectangular text area of the screen with left mouse button. Should work in any terminal screen (xterm, konsole, ...) under X, if not then try with 'Ctrl' + 'Shift' + 'Alt' or two-combination of these.

Get your outgoing IP address
should be very consistent cause it's google :-)

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 files containing string and open in vim
I often use "vim -p" to open in tabs rather than buffers.

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