Commands tagged redirecting output (12)

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Create a new file

chroot, bind mount without root privilege/setup
PRoot is a user-space implementation of chroot, mount --bind, and binfmt_misc. This means that users don't need any privileges or setup to do things like using an arbitrary directory as the new root filesystem, making files accessible somewhere else in the filesystem hierarchy, or executing programs built for another CPU architecture transparently through QEMU user-mode. Also, developers can use PRoot as a generic Linux process instrumentation engine thanks to its extension mechanism, see CARE for an example. Technically PRoot relies on ptrace, an unprivileged system-call available in every Linux kernel. https://github.com/cedric-vincent/PRoot

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" }

Compose 2 images to 1
Compose 2 images (foreground.jpg with background.jpg) into 1 (image.jpg), the numeric parameters stablish the size of the foreground.jpg image (96x96) and the position x,y (+250+70) relative to the background.jpg image. Images can be any format, jpg, png, bmp, etc...

Null a file with sudo

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by the excellent EVACopy http://evacopy.sourceforge.net

resize all images in a folder

Grabs a random image from "~/wallpapers" and sets as the background
don't bother spawning a bc process or counting the number of options, just pick a random one. 'sort -R' sorts randomly, so pick the top one.

Check disk for bad sectors
Checks HDD for bad sectors, just like scandisk or chkdisk under some other operating system ;-).

check open ports without netstat or lsof


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