How can I run UDP sockets in the background in an iPhone application?

6
votes

My iPhone application is using AsyncUdpSocket to handle a UDP socket. However, when my application goes into the background in iOS 4.0 and returns to the foreground, I am getting the following error:

Application 'MyAppName' exited abnormally with signal 13: Broken pipe

This is because my sockets are disconnected when my application goes to the background.

How can I avoid this and run UDP sockets in the background?

1
iphoneobjective-csocketsudp
Is your app registered as a VOIP or streaming audio app? Those might be the only types which keep a socket alive in the background. – hotpaw2
Yes..My info.plist have these properties "App plays audio,App provides Voice over IP services,App registers for location updates"... – S.P.
Problem is when application is background and phone is in locked state.. – S.P.
Did you ever get this sorted out? I'm having the same issue and am curious about your solution. – Kongress
@Kongress I used AsyncUdpSocket .Declared a CFReadStream and CFWriteStream variables globally and opened both streams.. If we opened a CFReadStream and CFWriteStream application will work as usual.. – S.P.

1 Answers

2
votes

This is not related to UDP. EPIPE only happens for "stream" file descriptors - Unix pipes and TCP sockets.

I'm guessing you have some sort of a control TCP connection which times out on the remote end when you go into background. You need to figure out how to keep it alive or re-connect when the app wakes up.

You can also handle (or ignore) EPIPE, see sigaction(2), and react to it accordingly on return from write(2).