How to save pointer in JavaScript and retrieve further

Question

I am using a dll at the server side for some computation . I am calling the dll from nodeJS using ffi module , so somewhere in the middle i need to save the address of the C pointer and used it further but I don't know how to save it so that i can pass it after some time to dll for executing operation on the same address.

does anyone have idea how to do this.

Answer 1

After searching a lot and trying different-2 scenarios finally i found a solution that how to store the address and retrieve in future for further operations :-

(Note:- here i am using ref, ffi modules) so for storing pointer , create a buffer that can hold pointer type like below

     const ref = require('ref');        
     const  ffi = require('ffi');

     var buf = ref.alloc('pointer');
     ref.writePointer(buf, 0, pointer);  // pointer or memory address

so here you store the memory address in buffer and where you want to use you can retrieve it from buffer like below:-

     memory_pointer = ref.readPointer(buf,0);   // buf is buffer which we created above, 0 for offset 

so now you get the memory_pointer so you can pass it to your function call using ffi module.