Can not build it

[xbee]

error info:

# github.com/raff/goble/xpc
xpc_wrapper.c:41:9: warning: implicit declaration of function 'Block_copy' is invalid in C99 [-Wimplicit-function-declaration]
xpc_wrapper.c:41:9: error: invalid block pointer conversion passing 'int' to parameter of type 'xpc_handler_t _Nonnull' (aka 'void (^)(xpc_object_t _Nonnull)')
/usr/include/xpc/connection.h:318:16: note: passing argument to parameter 'handler' here

[raff]

Can you give more details on how you are building / what's your environment ?

I am currently running MacOS 10.13.5 and XCode 9.4 with Go 1.10.2 and I don't get any error.

[xbee]

go version go1.10 darwin/amd64
XCode 9.4 
MacOS 10.13.6

[raff]

Block_copy should be defined in /usr/include/Block.h, included in line 4. Do you have that file and it's there a definition of Block_copy. Something like:

// Create a heap based copy of a Block or simply add a reference to an existing one.
// This must be paired with Block_release to recover memory, even when running
// under Objective-C Garbage Collection.
BLOCK_EXPORT void *_Block_copy(const void *aBlock)
__OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_3_2);

Do you have the XCode command line tools installed ? Try to follow the instructions here:
https://stackoverflow.com/questions/9353444/how-to-use-install-gcc-on-mac-os-x-10-8-xcode-4-4

[xbee]

Yes, I have installed Xcode command line tools. And my Block.h have Block_copy's define:

 // Create a heap based copy of a Block or simply add a reference to an existing one.
 // This must be paired with Block_release to recover memory, even when running
 // under Objective-C Garbage Collection.
 BLOCK_EXPORT void *_Block_copy(const void *aBlock)
      __OSX_AVAILABLE_STARTING(__MAC_10_6, __IPHONE_3_2);

.......

// Type correct macros
 
 #define Block_copy(...) ((__typeof(__VA_ARGS__))_Block_copy((const void *)(__VA_ARGS__)))
 #define Block_release(...) _Block_release((const void *)(__VA_ARGS__))

my gcc environment

> xcode-select --install
xcode-select: error: command line tools are already installed, use "Software Update" to install updates

> gcc -v
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
Apple LLVM version 9.1.0 (clang-902.0.39.2)
Target: x86_64-apple-darwin17.7.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin

[xbee]

I changed code from :

xpc_connection_t XpcConnect(char *service, uintptr_t ctx) {
    dispatch_queue_t queue = dispatch_queue_create(service, 0);
    xpc_connection_t conn = xpc_connection_create_mach_service(service, queue, XPC_CONNECTION_MACH_SERVICE_PRIVILEGED);

    // making a local copy, that should be made "persistent" with the following Block_copy
    //GoInterface ictx = *((GoInterface*)ctx);

    xpc_connection_set_event_handler(conn,
        Block_copy(^(xpc_object_t event) {
            handleXpcEvent(event, ctx); //(void *)&ictx);
        })
    );

    xpc_connection_resume(conn);
    return conn;
}

to next:

xpc_connection_t XpcConnect(char *service, uintptr_t ctx) {
    dispatch_queue_t queue = dispatch_queue_create(service, 0);
    xpc_connection_t conn = xpc_connection_create_mach_service(service, queue, XPC_CONNECTION_MACH_SERVICE_PRIVILEGED);

    // making a local copy, that should be made "persistent" with the following Block_copy
    //GoInterface ictx = *((GoInterface*)ctx);

    xpc_connection_set_event_handler(conn,
       ^(xpc_object_t event) {
            handleXpcEvent(event, ctx); //(void *)&ictx);
        }
    );

    xpc_connection_resume(conn);
    return conn;
}

then it build ok. Just remove Block_copy's wrapped.

[xbee]

But now when I run examples/basic/scanner/main.go, It will complained:

go run examples/basic/scanner/main.go
2018/09/06 09:39:57 Unhandled event: xpc.Dict{"kCBMsgId":4, "kCBMsgArgs":xpc.Dict{"kCBMsgArgState":5}}
^Csignal: interrupt

And it can not find any bluetooth devices that should be found.