Commands using grep (1,935)

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Output files without comments or empty lines
better integration. works on all Unices works one bash and ksh.

Create a bunch of dummy text files
Using the 'time' command, running this with 'tr' took 28 seconds (and change) each time but using base64 only took 8 seconds (and change). If the file doesn't have to be viewable, pulling straight from urandom with head only took 6 seconds (and change)

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

Manipulate the metadata when the photo was taken, this will shift with +15hours + 30min

Replace all tabs with spaces in an application
Note that this assumes the application is an SVN checkout and so we have to throw away all the .svn files before making the substitution.

convert mp3 into mb4 (audiobook format)
to convert a whole directory, put all mp3 files in a for loop $ for i in $(ls *mp3); do mpg123 -s $i | faac -b 80 -P -X -w -o ${i%mp3}m4b -; done

Download song from youtube for import into itunes (m4a format)
Last argument is the youtube link. Requires ffmpeg

list files recursively by size

Use tee + process substitution to split STDOUT to multiple commands
Using process substitution, we can 'trick' tee into sending a command's STDOUT to an arbitrary number of commands. The last command (command4) in this example will get its input from the pipe.

Emulating netcat -e (netcat-traditional or netcat-openbsd) with the gnu-netcat
Then just nc servername 2600 and ./script.sh kill the client with ctrl+c. You can reconnect several times. kill the server with exit


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