sharing a DNSServiceRef using kDNSServiceFlagsShareConnection won't work

Question

Hi, I don't like the title of this question but i couldn't come with anything better.

I'm building a client using dns-sd api from Bonjour. I notice that there is a flag called kDNSServiceFlagsShareConnection that it is used to share the connection of one DNSServiceRef.

Apple site says

For efficiency, clients that perform many concurrent operations may want to use a single Unix Domain Socket connection with the background daemon, instead of having a separate connection for each independent operation. To use this mode, clients first call DNSServiceCreateConnection(&MainRef) to initialize the main DNSServiceRef. For each subsequent operation that is to share that same connection, the client copies the MainRef, and then passes the address of that copy, setting the ShareConnection flag to tell the library that this DNSServiceRef is not a typical uninitialized DNSServiceRef; it's a copy of an existing DNSServiceRef whose connection information should be reused.

There is even an example that shows how to use the flag. The problem i'm having is when I run the program it stays like waiting for something whenever I call a function with the flag. Here is the code:

DNSServiceErrorType error;
DNSServiceRef MainRef, BrowseRef;

error = DNSServiceCreateConnection(&MainRef);
BrowseRef = MainRef;
//I'm omitting when I check for errors

error = DNSServiceBrowse(&MainRef, kDNSServiceFlagsShareConnection, 0, "_http._tcp", "local", browse_reply, NULL); 
// After this call the program stays waiting for I don't know what

//I'm omitting when I check for errors
error = DNSServiceBrowse(&BrowseRef, kDNSServiceFlagsShareConnection, 0, "_http._tcp", "local", browse_reply, NULL);
//I'm omitting when i check for errors
DNSServiceRefDeallocate(BrowseRef); // Terminate the browse operation
DNSServiceRefDeallocate(MainRef); // Terminate the shared connection

Any ideas? thoughts? suggestion?