How should i return struct pointer?

Question

I have been writing a game item system, I need to create a struct in function and return the pointer of it, however, I don't know how to write function header

my code;

typedef struct {
//some member
}Header;

int main()
{
    Header *head; //create an pointer to capture the address
    head= ItmStartUp();
    ...     //some code
    return 0;
}

Header *header itmStartUp(){ // This line is the root of problem I believe,
                             //but I don't know how to fix it

    Header *head = malloc (100*sizeof(*head)); //create an array of struct
    return head;                               //return that address 
}

when I compiling the code ,gcc return:

error: expected '=', ' , ' , ' ; ', 'asm' or 'attribute' before 'itmStartUp'|

I have been referencing these source. However, it doesn't work for me, what should i do if I want to return the pointer? Thank you

https://cboard.cprogramming.com/c-programming/20380-function-return-pointer-structure.html

Returning a struct pointer

I have changed the code, but it return conflicting types.... for ItmStartUp, no mater it is *head / head / &head, what have i done wrong? — Nilhope, Feb 09 '21 at 19:11

score 1 · Answer 1 · answered Feb 09 '21 at 19:26

You are getting a syntactic error here:

Header *header itmStartUp()
       ^^^^^^^___ unexpected stuff

Also, you need to define a prototype of the function before taking It into usage. Just to make it clear, an example code segment is as follows (read the comments):

typedef struct {
    int var;
} Header;

// Function is expected to return Header* type
Header* itm_startup() {
    Header *head = (void *)malloc(sizeof(Header));
    head->var = 10;

    // Returning the initialized 'head' (the type of Header*)
    return head;
}

int main(void) {
    // Calling the function to initialize
    Header *header = itm_startup();

    // Outputting the content of the 'header' pointer
    fprintf(stdout, "%d\n", header->var);

    return 0;
}

How should i return struct pointer?

1 Answers1