Commands by kennethjor (5)

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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Monitoring wifi connection by watch command (refresh every 3s), displaying iw dump info and iwconfig on wireless interface "wlan0"

Count lines of code across multiple file types, sorted by least amount of code to greatest
Gives you a nice quick summary of how many lines each of your files is comprised of. (In this example, we just check .c, .h, .php and .pl). Since we just use wc -l to count, you'll just get a very rough estimate of how many lines of actual code there are. Use a more sophisticated algorithm instead if you need to.

Record audio and video from webcam using ffmpeg
Record from a webcam, audio using ALSA encoded as MP3, video as MPEG-4.

Outputs a sorted list of disk usage to a text file
Recursively searches current directory and outputs sorted list of each directory's disk usage to a text file.

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"

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Diff files over SSH
Sometimes you need to compare two config files on different servers. Put the file names into the above script and let 'er rip.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Plaintext credentials sniffing with tcpdump and grep
Simple TCPDUMP grepping for common unsafe protocols (HTTP, POP3, SMTP, FTP)

Debian: Mark all dependent packages as manualy installed.
Debian: Mark all dependent packages as manually installed. So they are not automatically removed if you remove some meta package - like gnome-desktop-environment for example.

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Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.


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