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Ask for a password, the passwd-style
You can ask repeatedly for a non-blank password using this function: function read_password() { while [ ! -n "$USER_PASSWORD" ]; do read -s -p"Password: " USER_PASSWORD if [ ! -n "$USER_PASSWORD" ]; then echo "ERROR: You must specify a valid password, please try again" fi echo done } Also you can set a time out (in seconds) to write the password read -t 10 -s -p"Password: " USER_PASSWORD_VARIABLE if [ ! $? -eq 0 ]; then echo "Time out!" fi

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

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

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

Resets your MAC to a random MAC address to make you harder to find.
Next time you are leaching off of someone else's wifi use this command before you start your bittorrent ...for legitimate files only of course. It creates a hexidecimal string using md5sum from the first few lines of /dev/urandom and splices it into the proper MAC address format. Then it changes your MAC and resets your wireless (wlan0:0).

A bit of privacy in .bash_history
Don't track in history commands starting with whitespace. Moreover ignore duplicates from history. To be set in .bashrc ex. $ export HISTCONTROL=ignoreboth $   echo antani $   history|grep -c antani 0

Easily decode unix-time (funtion)
A shell function using perl to easily convert Unix-time to text. Put in in your ~/.bashrc or equivalent. Tested on Linux / Solaris Bourne, bash and zsh. using perl 5.6 and higher. (Does not require GNU date like some other commands)

Copy all files. All normal files, all hidden files and all files starting with - (minus).
./* is for copying files starting with - .[!.]* is for copying hidden files and avoiding copying files from the parent directory. ..?* is for copying files starting with .. (avoids the directory ..) /path/to/dir the path to the directory where the files should be copied Can also be used as a script. Input argument is /path/to/dir in tcsh, replace .[!.]* with .[^.]*

Get all these commands in a text file with description.
I tried out on my Mac, jot to generate sequence ( 0,25,50,..), you can use 'seq' if it is linux to generate numbers, need curl installed on the machine, then it rocks. @Satya

print all network interfaces' names and IPv4 addresses
ifconfig can't properly display interface's name longer 9 symbols,also it can't show IPs added thru ip command, so 'ip' should be used instead. This alias properly shows long names, bond interfaces and all interface aliases. loopback interface is ignored, since its IP is obvious


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