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Convert a script to one-liner
Opposite: Convert an one-liner to script: $ foo() { ; } ... $ typeset -f foo ... $ unset -f foo

encrypt whole line with ROT13 in vim

drop first column of output by piping to this

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Continue a current job in the background
Continue a current job in the background and detach it from current terminal

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" }

Use QEMU to create a hardware dual-boot without rebooting
After downloading an ISO image, assuming you have QEMU installed, it’s possible to boot an ISO image in a virtual machine and then install that ISO from within the virtual machine directly to a physical drive, bypassing the need to reboot. Simply pass the ISO image as the -cdrom parameter, followed by “format=raw,file=/dev/sdb” (replace /dev/sdb with the drive you want to install to) as the hard drive parameter (making absolutely certain to specify the raw format, of course). Once you boot into the ISO image with QEMU, just run the installer as if it were a virtual machine — it’ll just use the physical device as an install target. After that, you’ll be able to seamlessly boot multiple distros (or even other operating systems) at once.

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" }

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

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"


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