在C中返回结构指针数组的函数签名的语法是什么？

Question

I need a function to return an array of pointers to structs. What is the syntax for this? Conceptually I'm thinking struct my_struct *[] create_my_struct_table(int arr[], size_t length); But this does not work. I am not trying to return an array of struct my_struct but rather an array of struct my_struct * .

Answer 1

You cannot return an array in C. You can return a struct that contains an array (which may be an array of pointers). You can also return a pointer to an array, which must have a lifetime longer than the function that returns it, such as a static array or one returned from calloc() . If it is dynamically-allocated, the caller must free it once and only once. Or the caller can allocate the destination array and pass its address as an output parameter.

Answer 2

struct mystruct ** foo(struct mystruct **arrayOFpointers)
{

    int i =0;
    while(arrayOFpointers[i] != NULL)
    {
        //do something with *arrayOFpointers[i]
        i++;
    }
    return arrayOFpointers;
}
int main()
{
    int n = 10; // size
    struct mystruct *pointers[n];
    pointers[0] = (struct mystruct*)malloc(sizeof(struct mystruct));
    //allocate all other pointers in the array like this

    struct mystruct *processed_Pointers[n];

    processed_Pointers = foo(pointers);
return 0;
}