C Programming Function Parameters: Pass by Value
Last modified by Microchip on 2023/11/09 09:06
Parameters passed to a function are passed by value. Values passed to a function are copied into the local parameter variables. The original variable that is passed to a function cannot be modified by the function since only a copy of its value was passed.
1 int a, b, c;
2 int foo(int x, int y);
3
4 int main(void)
5 {
6 a = 5;
7 b = 10;
8 c = foo(a, b);
9 }
10 int foo(int x, int y)
11 {
12 x = x + (++y);
13 return x;
14 }
2 int foo(int x, int y);
3
4 int main(void)
5 {
6 a = 5;
7 b = 10;
8 c = foo(a, b);
9 }
10 int foo(int x, int y)
11 {
12 x = x + (++y);
13 return x;
14 }
The value of a is copied into x.
The value of b is copied into y.
The function does not change the value of a or b.