get IP Address in Lua

sockets networking lua coronasdk
christian Muller picture christian Muller · Aug 12, 2011 · Viewed 12.1k times · Source

i try to get the local IP from my device ( programming in Corona Lua )

till now I do with:

local myip = socket.dns.toip(socket.dns.gethostname())

but this only works on simulator

local client = socket.connect( "www.google.com", 80 )
local ip, port = client:getsockname()

but this only works when I have a Internet Connection

How could i get my local IP just in my Wifi without Internet

thx chris

Answer

basicer picture basicer · Jan 23, 2012

The ip of the interface you are looking for can change based on what IP address you are trying to talk to. The code below uses google's IP to select an interface and return the IP address. It works me for me using LUA/luasocket but I haven't tried it in corona.

require "socket"

local s = socket.udp()
s:setpeername("74.125.115.104",80)
local ip, _ = s:getsockname()
print(ip)

EDIT:

You shouldn't need internet in this case because you're not actually connecting to anything or otherwise sending any packets. You will however need the interface in question to actually have an IP.

Related questions

java.net.SocketException: Connection reset

I am getting the following error trying to read from a socket. I'm doing a readInt() on that InputStream, and I am getting this error. Perusing the documentation this suggests that the client part of the connection closed the connection. …

Read More
An existing connection was forcibly closed by the remote host

I am working with a commercial application which is throwing a SocketException with the message, An existing connection was forcibly closed by the remote host This happens with a socket connection between client and server. The connection is alive and …

Read More
What is the difference between a port and a socket?

This was a question raised by one of the software engineers in my organisation. I'm interested in the broadest definition.

Read More