Commands by n0a110w (2)

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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

Install pip with Proxy
Installs pip packages defining a proxy

How to get an absolute value
Whenever we are only interested in difference between two numbers and not the positive/negative values we can use this in script.

Picture Renamer

A command line calculator in Perl
Once I wrote a command line calculator program in C, then I found this... and added to it a bit. For ease of use I normally use this in a tiny Perl program (which I call pc for 'Perl Calculator') #!/usr/bin/perl -w die "Usage: $0 MATHS\n" unless(@ARGV);for(@ARGV){s/x/*/g;s/v/sqrt /g;s/\^/**/g}; print eval(join('',@ARGV)),$/; It handles square roots, power, modulus: $ pc 1+2 (1 plus 2) 3 $ pc 3x4 (3 times 4) 12 $ pc 5^6 (5 to the power of 6) 15625 $ pc v 49 ( square root of 49 ) 7 $ pc 12/3 (12 divided by 3) 4 $ pc 19%4 (19 modulus 4) 3 (you can string maths together too) $ pc 10 x 10 x 10 1000 $ pc 10 + 10 + 10 / 2 25 $ pc 7 x v49 49

Delete backward from cursor, useful when you enter the wrong password

Use vi commands to edit your command lines
If you spend all day editing in vi then switching your fingers to Emacs mode just for the command line can be difficult. Use set -o vi in your bash shell and enjoy the power of a real editor.

Runs previous command but replacing
Replaces the first instance of 'foo' with 'bar'. To replace all instances of 'foo' with 'bar': !!:gs/foo/bar/

ssh X tunneling over multiple ssh hosts (through ssh proxy)
Simply makes it possible to launch any X application residing on sshhost through sshproxy and display it on your screen where ever you are.

Determine what an process is actually doing


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