Commands by whoami (1)

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Find the real procesor speed when you use CPU scaling [cpuspeed]
We don't use CPU scaling, but just in case you do, there is something interesting to note. If you look at the /proc/cpuinfo, the speed listed is current running speed of the processors and not the real speed of the chip.

Trim png files in a folder
That should be a short as it can get.

Merge tarballs
Requires the GNU tar ignore zeros option. http://www.gnu.org/software/tar/manual/html_section/Blocking.html

processes per user counter
use Linux ;)

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

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

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

Watch how many tcp connections there are per state every two seconds.

Get Futurama quotations from slashdot.org servers
slashdot.org webserver adds an X-Bender or X-Fry HTTP header to every response!

Swap the two last arguments of the current command line
Say you just typed a long command like this: $ rsync -navupogz --delete /long/path/to/dir_a /very/long/path/to/dir_b but you really want to sync dir_b to dir_a. Instead of rewriting all the command line, just type followed by , and your command line will read $ rsync -navupogz --delete /very/long/path/to/dir_b /long/path/to/dir_a


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