Question

I found this program to run through strings and print them. I know there’s an error, but I’m not 100% sure what it is.

char *stringOptions[] = {"one", "two", "three"};

void incrementString(char *input) 
{
    static int i = 0;
    input = stringOptions[i % 3];
    i = (i + 1) % 3;
}

void print_string(void) 
{
    char *string = "initial";
    int i;

    for(i = 0; i < 3; ++i) 
    {
        incrementString(string);
        printf("%s ", string);
    }
}

It is supposed to print out: one two three

Sorry I don’t know more about it, it’s based on something I was trying to do, but I was unsuccessful reading through the strings. It is essential that this be in separate functions like this. Thanks,

Answer 1

input = stringOptions[i % 3];

this doesn’t do anything. Remember, C passes everything by value, so all you’re doing is setting the local copy of input to a new address. You probably want to pass a double pointer into the function and then set the dereferenced version:

void incrementString(char **input) {

...

*input = stringOptions[i%3];

then call it like:

incrementString(&string);

And also what zoidberg said about your loop.

for(i=0; i < 3; ++i) {

because the second part of a for loop is the condition on which it should continue to loop.