HTTPSocket: InternetAvailable?

General
#1

Using a socket, I know I can get a response to a post message.
I know I can trap a ‘connected’ event when it connects.

I’d like to know if an internet connection is available before I try rather post and sitting waiting for a ‘train that won’t come’
Is there a way to know if an internet connection is available?

On some machines, white or blacklisting can prevent my app from dialling home.

#2

I found out about this just the other day, Network.IsConnected

#3

Thats a handy tip.
I’ll probably still need to check if that tells me about my own app, or the machine as a whole.

#4

I guess a LAN will get you Network.IsConnected = True, but it won’t say the Internet is present. Checking if Internet connectivity exists remains necessary.

#5

On that page it notes that: This function is supported on Linux.

I have not tried it, but this looks like either an implication that it is only supported on Linux or it is a documentation oddity.

#6

[quote=231042:@Chris Carter]On that page it notes that: This function is supported on Linux.

I have not tried it, but this looks like either an implication that it is only supported on Linux or it is a documentation oddity.[/quote]

It works fine on Mac. But as I suspected, it just reports the presence of connectivity. A local router is seen as network.

To make sure the Internet is present, the simplest I found is to shell

ping google.com

If there is no Internet, result is :

ping: cannot resolve google.com: Unknown host

otherwise it gives something like :

PING google.com (216.58.211.78): 56 data bytes 64 bytes from 216.58.211.78: icmp_seq=0 ttl=55 time=25.279 ms

In Windows,

Ping request could not find host google.com. Please check the name and try again

or

Pinging google.com [173.194.45.46] with 32 bytes of data: Reply from 173.194.45.46: bytes=32 time=25ms TTL=55

Seems like a nice cross platform way.

#7

I found that just asking for my homepage with an httpsocket.GET with a timeout looks like the easiest way to check.

If I get a status of 200, the site is there, and I can talk to it, so I can then proceed to risk a POST.

dim h as new HTTPSocket call h.Get("http://www.example.com/", 30) if h.HTTPStatusCode <> 200 then msgbox "There may be trouble ahead, but while there's moonlight..." end if

#8

And what about:
Dim http As New HTTPSocket
HTTP.Address = “www.apple.com”
http.port = 80
http.Connect
if http.LastErrorCode = 0 then
//do something
//MsgBox “Connected”
end if
http.close

It SEEMS quicker that Jeff’s code. But is it 100% reliable?
Thanks.

#9