Using callback function in C app with swift library

[jeffdev]

I have a C app on MacOS and I call functions in a swift dylib. I want to register callback functions in C to be called in swift when some event happens. Is there some example on how to do this?

I have this callback declaration in C:
typedef int (*event_cb_t)(int evt, char *data);

I want to register the callback in swift like this:
//callback function defined in C
int callback(int evt, char *data)
{
return 0;
}

registerCb(callback); //swift exported function

[eskimo (Quinn “The Eskimo!”)]

AFAIK things haven’t changed since this thread.

Share and Enjoy

Quinn “The Eskimo!” @ DTS @ Apple

[Fabio_Kaminski]

Hey, i just did a answer into this same question but with C++. I have pointed a possible solution there and i think it can work for your case too.

I hope it helps.

Calling Swift Code from C++

First, while it looks Swift will have a great support for C++ in the near future, for now you will need to create simple C wrappers to your interfaces. I will tell you what i do here: I register a callback in swift that is a c callback, but always pass a 'state' option to the C function. like this: I define a callback structure in C like (thing.h) C++: suppose you have this class class Thing { public: bool A(int x, int y); bool B(int x, int y, int z); bool C(int x); }; thin…