Commands by Mahrud (1)

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Quick key/value display within /proc or /sys
Within /proc and /sys there are a lot of subdirectories, which carry pseudofiles with only one value as content. Instead of cat-ing all single files (which takes quite a time) or do a "cat *" (which makes it hard to find the filename/content relation), just grep recursively for . or use "grep . /blabla/*" (star instead of -r flag). For better readability you might also want to pipe the output to "column -t -s : ".

log rm commands
Sometimes, it is annoying to find your files or directories missing. If you want to log all the rm commands you can put this in /etc/profile.

show current directory
Opens a file or URL in the user's preferred application.

Zip a directory on Mac OS X and ignore .DS_Store (metadata) directory
If you want to generate a cross-platform compatible zip file and ignore the Finder's hidden metadata directory

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"

Kill any process with one command using program name
See also: killall

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

Securely destroy data (including whole hard disks)
GNU shred is provided by the coreutils package on most Linux distribution (meaning, you probably have it installed already), and is capable of wiping a device to DoD standards. You can give shred any file to destroy, be it your shell history or a block device file (/dev/hdX, for IDE hard drive X, for example). Shred will overwrite the target 25 times by default, but 3 is enough to prevent most recovery, and 7 passes is enough for the US Department of Defense. Use the -n flag to specify the number of passes, and man shred for even more secure erasing fun. Note that shredding your shell history may not be terribly effective on devices with journaling filesystems, RAID copies or snapshot copies, but if you're wiping a single disk, none of that is a concern. Also, it takes quite a while :)

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"

Get the 10 biggest files/folders for the current direcotry


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