Commands by CoolHand (1)

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Ride another SSH agent
Must be done as root - will cause subsequent ssh connections to use the identities available via the [user]'s agent socket.

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" }

Get your external IP address if your machine has a DNS entry
Easy way to see your real external IP

Reboot without being root
For more, See: https://github.com/noureddin/bash-scripts/blob/master/user_scripts/userpower

Rapidly invoke an editor to write a long, complex, or tricky command
Allows you to edit your command using your chosen editor. Works in bash with "set -o vi".

Display laptop battery information

Using netcat to copy files between servers
It bypasses encryption overhead of SSH and depending on configuration can be significantly faster. It's recommended to use only in trusted networks.

Faster find and move using the find and xargs commands. Almost as fast as locate.
Only tested on Linux Ubunty Hardy. Works when file names have spaces. The "-maxdepth 2" limits the find search to the current directory and the next one deeper in this example. This was faster on my system because find was searching every directory before the current directory without the -maxdepth option. Almost as fast as locate when used as above. Must use double quotes around pattern to handle spaces in file names. -print0 is used in combination with xargs -0. Those are zeros not "O"s. For xargs, -I is used to replace the following "{}" with the incoming file-list items from find. Echo just prints to the command line what is happening with mv. mv needs "{}" again so it knows what you are moving from. Then end with the move destination. Some other versions may only require one "{}" in the move command and not after the -I, however this is what worked for me on Ubuntu 8.04. Some like to use -type f in the find command to limit the type.

Number of files in a SVN Repository
This command will output the total number of files in a SVN Repository.

Flush DNS cache in MacOS 10.5

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