Commands using uniq (255)

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Count number of files in a directory

Run a command when a file is changed

Have netcat listening on your ports and use telnet to test connection
This will start a netcat process listening on port 666. If you are able connect to your your server, netcat will receive the data being sent and spit it out to the screen (it may look like random garbage, so you might want to redirect it to a file).

Find out when your billion-second anniversary is (was).
Replace 12/31/1970 with your birth date.

Generate 10 pronunciable passwords
A great password generation tool. http://www.adel.nursat.kz/apg/

Create a random file of a certain, and display progress along the way.
SIZE is the number of gigabytes and the file name is at the end. Random data is generated by encrypting /dev/zero, similar to other techniques posted on here.

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

Validate date, also a date within a leap year
Important to know: a valid date will return 0, otherwise 1!

Monitor dynamic changes in the dmesg log.
Other logs can be monitored similarly, e.g. $ watch "tail -15 /var/log/daemon.log"

Doing some floating point calculations with rounding (e.g. at the 3rd decimal)


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