Commands by _john (5)

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Create a system overview dashboard on F12 key
Command binds a set of commands to the F12 key. Feel free to alter the dashboard according to your own needs. How to find the key codes? Type $ read Then press the desired key (example: F5) $ ^[[15~ Try $ bind '"\e[15~"':"\"ssh su@ip-address\C-m""" or $ bind '"\e[16~"':"\"apachectl -k restart\C-m"""

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" }

how to export a table in .csv file
Exports the result of query in a csv file

display a one-liner of current nagios exit statuses. great with netcat/irccat

List your MACs address

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Create a tar file with the current date in the name.

List all users and groups

Generate list of words and their frequencies in a text file.

Create a tar of directory structure only
The original suggestion did not work for me, when operating on folders located on an external mount (ie other than the root device) in Ubuntu. A variation using xargs does the trick.


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