Commands tagged awk (348)

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Generate random valid mac addresses
First set the variable $hexchars: $hexchars="0123456789ABCDEF" Change the number in the first for loop if you need less then 1200 mac addresses

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.

check open ports without netstat or lsof

Detect encoding of a text file
This command gives you the charset of a text file, which would be handy if you have no idea of the encoding.

list all files in a directory, sorted in reverse order by modification time, use file descriptors.
It's both silly, and infinitely useful. Especially useful in logfile directories where you want to know what file is being updated while troubleshooting.

Get a range of SVN revisions from svn diff and tar gz them
Handy when you need to create a list of files to be updated when subversion is not available on the remote host. You can take this tar file, and upload and extract it where you need it. Replace M and N with the revisions specific to yours. Make sure you do this from an updated (svn up) working directory.

Tell what is encoded in a float, given its HEX bytes
It handles all possible combination of the hex bytes, including NaNs, Infinities, Normalized and Subnormal Numbers... $ This crazy DC stuff spent me a few days to write, optimize, polish and squeeze so that it works within the tight 255 character bound... $ You can modify it easily for other IEEE754 numbers, say, half, double, double-extended, quadruple $ (I hope someone will find this useful and submit more dc code to commandlinefu!)

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

Given $PID, print all child processes on stdout
Simpler.

Multi line grep using sed and specifying open/close tags
This line does not include your closing tag in the output.


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