How to use a native C function as callback function in jswrap functions?

[espruino-discuss]

Posted at 2017-03-23 by Aifer

In a C native module, I want to call other jswrap functions and asign my C function as the callback.

How to do that?
For example,
void mycallback();

void mycallback(){
    jsiConsolePrint("Hello world");
}
jswrap_net_connect(JsVar *options, JsVar *callback, SocketType socketType); // here I want asign mycallback( ) as the callback

[espruino-discuss]

Posted at 2017-03-23 by @gfwilliams

You need to do something like this: https://github.com/espruino/Espruino/blob/master/src/jswrap_promise.c#L83

Note the JSWAT_* enums determine what arguments the function takes. Just use JSWAT_VOID in your case.

---

Posted at 2017-03-23 by Aifer

@gfwilliams
Thanks.

Is there a document which explains the usage of jsvLock and jsvUlock?

Or, some documets describe the mechanism of native code?

---

Posted at 2017-03-23 by @gfwilliams

Not really, no. You'd need to look at other code, or there are some good threads on this forum. Also worth looking at http://www.espruino.com/Internals

However, I can't assist you - especially as you're not using one of the official Espruino boards. If you're doing this for a company and they need assistance then I can do consultancy work.

---

Posted at 2017-03-23 by Aifer

@gfwilliams
Thanks a lot.

I'm making a toy for my kid. I like javascript. Espruino makes it easy to write JS code for MCU. It's a wonderful platform.

Thanks again.