Commands by Rudolf (1)

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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"

Pick a random image from a directory (and subdirectories) every thirty minutes and set it as xfce4 wallpaper
Change your wallpaper every thirty minutes (or however long you like, I suppose) to a randomly selected image in a directory and subdirectories. Bear in mind this is not safe to use if anyone else has write access to your image directory.

scp file from hostb to hostc while logged into hosta
While at the command line of of hosta, scp a file from remote hostb to remote hostc. This saves the step of logging into hostb and then issuing the scp command to hostc.

Get shellcode of the binary using objdump
Anyone can make the command smaller & easier? :)

Retry the previous command until it exits successfully

Watch active calls on an Asterisk PBX
Only the number of calls nothing else.

identify exported sonames in a path
This provides a list of shared object names (sonames) that are exported by a given tree. This is usually useful to make sure that a given required dependency (NEEDED entry) is present in a firmware image tree. The shorter (usable) version for it would be $ scanelf -RBSq -F "+S#f" But I used the verbose parameters in the command above, for explanation.

SoX recording audio and trimming silence
Records audio from your mic in FLAC (Free Lossless Audio Codec) format, starts only after it detects at least 0.1 seconds of noise and stops after 1 second of silence. You can adjust the percent values (sensitivity) to best fit your microphone and voice (0.1% if you have a great quality mic, higher if you don't, 0% does not trim anything). Useful for speech recognition in conjunction with my previous command titled 'Google voice recognition "API"' (http://www.commandlinefu.com/commands/view/8043/google-voice-recognition-api).

Clean up display when the bash prompt is displayed
This will cause bash to fix a garbled terminal before the prompt is printed. For example, if you cat a file with nonprintable character sequences, the terminal sometimes ends up in a mode where it only prints line drawing characters. This sequence will return the terminal to the standard character set after every command.

Live stream a remote audio device over ssh using only ffmpeg
Change parameter 'plughw:0,0' in accordance with your audio device. To learn 'plughw' option, type the command aplay -l.


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