Code:
//Create array
var *myarray = sys_malloc(sizeof(var)*arraylength);

//Resize array
var *temparray = sys_malloc(sizof(var)*newlength);
memcpy(temparray, myarray, sizeof(float)*arraylength);
sys_free(myarray);
myarray = temparray;

//Access array
myarray[10] = 100;


alternatively you can use malloc and realloc, but that also means that you have to free it when closing the engine.

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