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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

Selecting a random file/folder of a folder
Also looks in subfolders

Print all lines between two line numbers
This command uses awk(1) to print all lines between two known line numbers in a file. Useful for seeing output in a log file, where the line numbers are known. The above command will print all lines between, and including, lines 3 and 6.

Display text as though it is being typed out in real time
Pipe Viewer allows you to monitor the progress of a data transfer or command, or to show the time elapsed, among other things. In this use, it limits the transfer rate of the echo command to 10 bytes per second, making your text appear to be typed out in real time as in Hollywood movies. Fun!

Do some Perl learning...
Prerequisites: module Pod::Webserver installed. You can install it typing: $ sudo perl -MCPAN -e 'install Pod::Webserver' You can replace elinks with your fav browser. For FF: $podwebserver& sleep 2; firefox -remote 'openurl( http://127.0.0.1:8020/, new-tab )' If you have Firefox open, this will pop-up the index web in a new tab.

print file without duplicated lines using awk
This create an array 'a' with wole lines. only one occurrence of each line - Not Get lines ++ !

!* Tells that you want all of the *arguments* from the previous command to be repeated in the current command
Example: touch file{1,2,3}; chmod 777 !*

check open ports (both ipv4 and ipv6)
While `lsof` will work, why not use the tool designed explicitly for this job? (If not run as root, you will only see the names of PID you own)

Perl oneliner to print access rights in octal format
This prints file access rights in octal - useful when "stat" is unavailable.

Compare two files side-by-side
I found out about this from Unix Power Tools, and thought it was pretty useful. Use the -w option to change the width of the output, and the -s option to suppress lines that are the same in both files.


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