This code is incorrect but it tells what I am trying to do
char* p = EM_ASM(
var a = new ArrayBuffer(8);
return a;
);
What is the correct way of getting a C pointer of that javascript arrayBuffer?
I only want to read the arrayBuffer not write
As far as I'm aware, there's no direct way of returning an array from some inline JavaScript (although there is a way of returning read-only arrays from JavaScript wrapped C functions, see this answer). What you can do instead is malloc space for the array in a C function, pass the address to the inline Emscripten, and use the Emscripten JavaScript function writeArrayToMemory to copy your JavaScript array into the malloced memory. Something like this...
char *a = malloc(4);
EM_ASM_INT({
var v1 = new Uint8Array([2,4,6,8]);
writeArrayToMemory(v1, $0)
}, a);
printf("the array is [%d, %d, %d, %d]\n", a[0], a[1], a[2], a[3]);
