Commands using head (314)

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a function to find the fastest DNS server
http://public-dns.info gives a list of online dns servers. you need to change the country in url (br in this url) with your country code. this command need some time to ping all IP in list.

convert from decimal to hexadecimal
Use the standard calculator bc to convert decimals to hex

clear MyDNS-ng cache
Occasionally, to force zone updating, cache flush is necessary. This command is better than restart the mydns daemon.

get all Amazon cloud (amazonws etc) ipv4 subnets

ignore hidden directory in bash completion (e.g. .svn)

Find the package that installed a command

List only executables installed by a debian package
Safe for whitespaces in names.

Simple XML tag extract with sed
Limited, but useful construct to extract text embedded in XML tags. This will only work if bar is all on one line. If nobody posts an alternative for the multiline sed version, I'll figure it out later...

Extract public key from private
This will extract the public key that is stored in the private key using openssl.

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


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