How to change value of variable passed as argument?

Question

How to change value of variable passed as argument in C? I tried this:

void foo(char *foo, int baa){
    if(baa) {
        foo = \"ab\";
    } else {
                


        

Answer 1

You question is titled in a generic way. You've already got answers for your specific problem. I'm going to add couple of illustrative examples for int and double types.

#include 

void incrementInt(int* in, int inc)
{
   *in += inc;
}

void incrementDouble(double* in, double inc)
{
   *in += inc;
}

int main()
{
   int i = 10;
   double d = 10.2;

   printf("i: %d, d: %lf\n", i, d);

   incrementInt(&i, 20);
   incrementDouble(&d, 9.7);

   printf("i: %d, d: %lf\n", i, d);
}

Output:

i: 10, d: 10.200000
i: 30, d: 19.900000