Commands by erdnaxeli (3)

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

Apply fade effect to a audio
fade [type] fade-in-length [stop-time [fade-out-length]] Apply a fade effect to the beginning, end, or both of the audio. An optional type can be specified to select the shape of the fade curve: q for quarter of a sine wave, h for half a sine wave, t for linear (`triangular') slope, l for logarithmic, and p for inverted parabola. The default is logarithmic. A fade-in starts from the first sample and ramps the signal level from 0 to full volume over fade-in-length sec? onds. Specify 0 seconds if no fade-in is wanted. For fade-outs, the audio will be truncated at stop-time and the signal level will be ramped from full volume down to 0 starting at fade-out-length seconds before the stop-time. If fade-out-length is not specified, it defaults to the same value as fade-in-length. No fade-out is performed if stop-time is not specified. If the file length can be determined from the input file header and length-changing effects are not in effect, then 0 may be specified for stop-time to indicate the usual case of a fade-out that ends at the end of the input audio stream. All times can be specified in either periods of time or sample counts. To specify time periods use the format hh:mm:ss.frac format. To specify using sample counts, specify the number of samples and append the letter `s' to the sample count (for example `8000s').

calculate md5 sums for every file in a directory tree
an alternative

Replace duplicate files by hardlinks

Give {Open,True}Type files reasonable names
Just a quick hack to give reasonable filenames to TrueType and OpenType fonts. I'd accumulated a big bunch of bizarrely and inconsistently named font files in my ~/.fonts directory. I wanted to copy some, but not all, of them over to my new machine, but I had no idea what many of them were. This script renames .ttf files based on the name embedded inside the font. It will also work for .otf files, but make sure you change the mv part so it gives them the proper extension. REQUIREMENTS: Bash (for extended pattern globbing), showttf (Debian has it in the fontforge-extras package), GNU grep (for context), and rev (because it's hilarious). BUGS: Well, like I said, this is a quick hack. It grew piece by piece on the command line. I only needed to do this once and spent hardly any time on it, so it's a bit goofy. For example, I find 'rev | cut -f1 | rev' pleasantly amusing --- it seems so clearly wrong, and yet it works to print the last argument. I think flexibility in expressiveness like this is part of the beauty of Unix shell scripting. One-off tasks can be be written quickly, built-up as a person is "thinking aloud" at the command line. That's why Unix is such a huge boost to productivity: it allows each person to think their own way instead of enforcing some "right way". On a tangent: One of the things I wish commandlinefu would show is the command line HISTORY of the person as they developed the script. I think it's that conversation between programmer and computer, as the pipeline is built piece-by-piece, that is the more valuable lesson than any canned script.

Inserts the results of an autocompletion in the command line
Pressing ESC then * will insert in the command line the results of the autocompletion. It's hard to explain but if you look the sample output or do $ echo ESC * you will understand quickly. By the way, few reminders about ESC : - Hold ESC does the same thing as tab tab - 'ESC .' inserts the last argument of last command (can be done many times in order to get the last argument of all previous commands)

Get lines count of a list of files
This command gives you the number of lines of every file in the folder and its subfolders matching the search options specified in the find command. It also gives the total amount of lines of these files. The combination of print0 and files0-from options makes the whole command simple and efficient.

extract email addresses from some file (or any other pattern)

Network Folder Copy with Monitoring ( tar + nc + pv )
Transfer tar stream thru nc with pv montoiring taken from: http://www.catonmat.net/blog/unix-utilities-pipe-viewer/

get the top 10 longest filenames


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