Commands tagged unix (65)

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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

FInd the 10 biggest files taking up disk space

This will allow you to browse web sites using "-dump" with elinks while you still are logged in
README: This require you to login on facebook with elinks without using '-dump' first time and when you have logged in you will then be able to dump all data from facebook without any advanced combos, dump is all you need for see all your friends newsfeed or whatever you wish to view in cli/terminal. Facebook is just an example, same requirements for all websites that have a login form.

use xxd to create the wake on lan magicpacket and write to pcap file
just set macdst to the mac address of the system you wish to wake up, the macsrc is optional but helps use tcpreplay to broadcast or wireshark to view

Backup all MySQL Databases to individual files

See entire packet payload using tcpdump.

Remove duplicate rows of an un-sorted file based on a single column
$F[0] filters using first word. $F[1] - 2nd, and so on.

Use /dev/full to test language I/O-failsafety
The Linux /dev/full file simulates a "disk full" condition, and can be used to verify how a program handles this situation. In particular, several programming language implementations do not print error diagnostics (nor exit with error status) when I/O errors like this occur, unless the programmer has taken additional steps. That is, simple code in these languages does not fail safely. In addition to Perl, C, C++, Tcl, and Lua (for some functions) also appear not to fail safely.

floating point operations in shell scripts
using bc is for sissies. dc is much better :-D Polish notation will rule the world...

Rename a file with a random name
Give files a random name (don't ask why :-) The function will rename files but maintain their extensions. BUG: If a file doesn't have an extension it will end up with a dot at the end of the name. The parameter '8' for pwgen controls the length of filenames - eight random characters.


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