UDP Communication in iOS

Development Programming & Scripting
1

Hello , I got a problem when I open my App in iPad. It uses the UDP Communication in GitHub , and it works well in two windows computers’ communications. But when I package to iOS ,and open in iPad, it breaks down right now after I open it.
When I disable the following codes , my App will not break down in iPad. But communication function is disable too.

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I found that the UdpMessaging plugin used the same method.

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What should we do to solve this problem…Great appreciation!

2

Maybe it just failed to build a udp socket.

3

确实是这样的。UpdSocket在Ipad上没有创建成功。但是在PC上测试是可以的。TT

4

SenderSocket = FUdpSocketBuilder(*SocketName) .AsReusable() .WithBroadcast();

UdpSocketBuilder created failed in iPad. So SenderSocket is NULL.
What should I do to make it create successful in iPad…Great appreciation~

5

I would like suggest you to take a look of ISocketSubsystem::GetLastErrorCode() first.

Normally you may got error like EACCES, which means your app socket permission denied. Then you may have to check root access or there is another app using same address.

6

没有创建成功的可能性很多，权限问题，端口被占用等等。
Socket属于底层功能，PC上能过 并不意味着手机平台上能过，甚至不同的IOS版本都会给你不同的结果。所以这才是开始。。。。

7

心好痛。。。蟹蟹。。。

8

I have found the reason , and use a method to avoid this problem(it is not a good solution , and I will keep going on UDP and TCP communication problem).

What I do is to rewrite the UdpSocketBuilder.h and disable the following code :
Error = !Socket->SetMulticastLoopback(MulticastLoopback) || !Socket->SetMulticastTtl(MulticastTtl);

It seems that “Multicast” will lead to some problem in iOS, and I am not able to solve it now .So I have to avoid it.

And I rewrite the following codes:

if (Socket!=NULL)
		{
			int32 OutNewSize;

			if (ReceiveBufferSize > 0)
			{
				Socket->SetReceiveBufferSize(ReceiveBufferSize, OutNewSize);
			}

			if (SendBufferSize > 0)
			{
				Socket->SetSendBufferSize(SendBufferSize, OutNewSize);
			}
		}

the above is all in MyUdpSocketBuilder.h which I copy from UdpSocketBuilder.h.

And I delete the function " WithBroadcast()" in UDPSender.cpp:

SenderSocket = FMyUdpSocketBuilder(*SocketName)
		.AsReusable();

All the above is according to the Plugin “udp-ue4-plugin-win64” made by AlekseiTepljakov , which is also according to RAMA’s working.

My version is 4.20

I will keep learning to solve the left problems.
Thanks to henryLiu~~~
谢啦老哥~~~