If you rewrote the code to

void function1()
{
int variable = 5;
function2(variable);
}


void function2 (int var)
{
var = 10;
return;
}

It would not work , function2 gets passed a copy of the variable which it can alter. It will not alter "variable".

If you are using C++ and not C you can use refernces which would make the code look like

void function2 (int & var)
{
var = 10;
return;
}

This code would change "variable" just like the pointer version.

Quote:Original post by Greek89
Instead of using "&variable" and "*var" as parameters, couldnt we just use "variable" and "var"?

If you did that, then the information "5" would be passed. function2 would have no idea where that 5 came from. There would be no connection to variable. Changes wouldn't be reflected to the caller.

If instead you pass &variable, you pass the information where the variable is stored. Basically, you pass "the variable itself", if you will, thus function2 is able modify it.