Commands by ishi444 (0)

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How much RAM is Apache using?
Display the amount of memory used by all the httpd processes. Great in case you are being Slashdoted!

list block devices
Shows all block devices in a tree with descruptions of what they are.

List the size (in human readable form) of all sub folders from the current location
Simple and easy to remember. -h is human, -d1 = depth 1. disk usage, human, depth 1

Copy the sound content of a video to an mp3 file
-vn removes tha video content, the copy option tells ffmpeg to use the same codec for generating the output

Convert control codes to visible Unicode Control Pictures
Converts control codes and spaces (ASCII code ≤ 32) to visible Unicode Control Pictures, U+2400 ? U+2420. Skips \n characters, which is probably a good thing.

Get me yesterday's date, even if today is 1-Mar-2008 and yesterday was 29-Feb-2008
Fool date by setting the timezone out by 24 hours and you get yesterday's date. Try TZ=XYZ-24 to get tomorrow's date. I live in TZ=GMT0BST so you might need to shift the number 24 by the hours in your timezone.

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

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Random quote from Borat -- no html parsing
Turns out smacie.com has a text file containing every single one of the borat quotes, each one on a newline. This makes it very convenient, as this can be done without any sed-parsing, and uses less bandwitdth! Note that borate quotes are quite offensive, much more so than "fortunes-off"!

Copy sparse files
This causes cp to detect and omit large blocks of nulls. Sparse files are useful for implying a lot of disk space without actually having to write it all out. http://en.wikipedia.org/wiki/Sparse_file You can use it in a pipe too: $ dd if=/dev/zero bs=1M count=5 |cp --sparse=always /dev/stdin SPARSE_FILE

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