var c_trace_ent(ENTITY* trace_ent, VECTOR* from, VECTOR* to, long flags, CONTACT * _hit)
{
	var _group = trace_ent.group; // set a backup value
	
	trace_ent.group = 1;
	c_ignore(0);
	
	var _dist = c_trace(from, to, flags);
	
	if(_hit) _hit = hit; // pass hit information (if _hit exists)
	
	trace_ent.group = _group;
	
	return _dist; // return trace distance
}

if(_hit) _hit = hit;

c_ignore(0);

var test_fnc(var * var_ptr)
{
	*var_ptr = 25;
	return *var_ptr * 2;
}

[...]

	var var_a = 0;
	var var_b = test_fnc(var_a);