Commands by vermiculus (1)

What's this? is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Stream and copy a video from lan
Requires a listening port on HOST eg. "cat movie.mp4 | nc -l 1356 " (cat movie.mp4 | nc -l PORT) Useful if you're impatient and want to watch a movie immediately and download it at the same time without using extra bandwidth. You can't seek (it'll crash and kill the stream) but you can pause it.

create an screenshot, upload it to your server via scp and then open that screenshot in firefox
I often need to send screenshots to other people to explain settings and whatever. So I created this oneline which I use to create the screenshot with imagemagik, upload it via scp to my server and then the command opens an firefox tab with the screenshot. The screenshot can be a region or a window. You just have to replace the parts beginning with YOUR.

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 a server is up. If it isn't mail me.
For some reason the 2&>1 does not work for me, but the shorter stdout/stderr redirection >& works perfectly (Ubuntu 10.04).

Cut out a piece of film from a file. Choose an arbitrary length and starting time.
With: -vcodec, you choose what video codec the new file should be encoded with. Run ffmpeg -formats E to list all available video and audio encoders and file formats. copy, you choose the video encoder that just copies the file. -acodec, you choose what audio codec the new file should be encoded with. copy, you choose the audio encoder that just copies the file. -i originalfile, you provide the filename of the original file to ffmpeg -ss 00:01:30, you choose the starting time on the original file in this case 1 min and 30 seconds into the film -t 0:0:20, you choose the length of the new film newfile, you choose the name of the file created. Here is more information of how to use ffmpeg:

Run a ext4 file system check and badblocks scan with progress info
Nothing fancy, just a regular filesystem scan that calls the badblocks program and shows some progress info. The used options are: -c ? check for bad sectors with badblocks program -D ? optimize directories if possible -f ? force check, even if filesystem seems clean -t ? print timing stats (use -tt for more) -y ? assume answer ?yes? to all questions -C 0 ? print progress info to stdout /dev/sdxx ? the partition to check, (e.g. /dev/sda1 for first partition on first hard disk) NOTE: Never run fsck on a mounted partition!

backup your entire hosted website using cPanel backup interface and wget
this will connect to your hosted website service through the cPanel interface and use its backup tool to backup and download the entire website, locally. (do not forget to replace : YourUsername , YourPassword and YourWebsiteUrl for it to work )

add static arp entry to default gateway, arp poison protection

List directories recursively showing its sizes using only ls and grep
ls -lhR Lists everithing using -l "long listing format" wich includes the space used by the folder. Displays it in -h "human readable form" (i.e. 2.2G, 32K), and -R recurses subfolders. grep -e using a regex, show lines containing the word "total" or a ":" at the end of the line (those with the name of the folder) only.

Get your outgoing IP address

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