Commands by noisy (5)

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View internet connection activity in a browser
The output of lsof is piped to txt2html which converts it to html. # Perl module HTML::TextToHTML needed

Docker.io Stop and Remove all processes
Will stop all running containers, then remove all containers **This isn't for selectively handling containers, it removes everything**

Backup your hard drive with dd
This will create an exact duplicate image of your hard drive that you can then restore by simply reversing the "if" & "of" locations. $ sudo dd if=/media/disk/backup/sda.backup of=/dev/sda Alternatively, you can use an SSH connection to do your backups: $dd if=/dev/sda | ssh [email protected] dd of=~/backup/sda.backup

Find out if a module is installed in perl
Shows the path if the module is installed or exit quietly (to simply avoid the 'No documentation found' msg).

Use file(1) to view device information
file(1) can print details about certain devices in the /dev/ directory (block devices in this example). This helped me to know at a glance the location and revision of my bootloader, UUIDs, filesystem status, which partitions were primaries / logicals, etc.. without running several commands. See also: $ file -s /dev/dm-* $ file -s /dev/cciss/* etc..

Sort movies by length, longest first
handles file names with spaces and colons, fixes sort (numeric!), uses mplayer, same output format as other alternatives

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"

Check if a command is available in your system
Usefull to detect if a commad that your script relies upon is properly installed in your box, you can use it as a function function is_program_installed() { type "$1" >/dev/null } Invoke it and check the execution code is_program_installed "dialog" if [ ! $? -eq 0 ]; then echo "dialog is not installed" exit 1 fi

list block devices
Shows all block devices in a tree with descruptions of what they are.

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" }


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