[Mike Betts]

Originally Posted by Keith Watson

The original code just modifies a local copy of the argument passed in. You need to "pass by reference". Typical usage is:

void Drive(int& motor, unsigned char speed)
{
	// modify inputted speed
	motor = speed;
}
 
Drive(pwm01, 100);

Mark's example works but is less common in usage. It takes the address of the variable, passes it in as a pointer, then dereferences the pointer.

Keith,

I think that you are mixing C++ with C. in C++, "int&" is a pass by reference. In C there is no pass by reference only pass by value and a pointer is the only way to do it.

Mike



To All,

Mark's post is correct. Please read K&R chapter 5 before sliding down the perilous and provocative path of pointers.

Mike