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Generate QR code for a WiFi hotspot
Prompts for network name (SSID) and password, and generates (as qr-wifi.png) a WiFi QR code (e.g. "WIFI:S:mynet;T:WPA;P:mypass;;" for mynet/mypass). Dependencies [sudo apt-get install]: qrencode zenity

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

Cleanly manage tempfiles in scripts
Cleanly create tempfiles using mktemp and remove them using traps instead of removing them in the end of the script. This way, you make sure the tempfiles are removed properly even if the script is killed or interrupted. For a user script in KDE4, you can set TMPROOT using : $ TMPROOT=$(kde4-config --path tmp)

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

Recursive Ownership Change
Changing files ownership in a directory recursivley from a user to another

apache statistics

capture mysql queries sent to server

Rename files in batch

exit without saving history
this exits bash without saving the history. unlike explicitly disabling the history in some way, this works anywhere, and it works if you decide *after* issuing the command you don't want logged, that you don't want it logged ... $$ ( or ${$} ) is the pid of the current bash instance this also works perfectly in shells that don't have $$ if you do something like $ kill -9 `readlink /proc/self`

vimdiff local and remote files via ssh
Lifted from http://linux.spiney.org/remote_diff_with_vim_and_ssh which points out credits for the inspiration.


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