structure identifier is not defined even though it is-CodePudding

I have a school project where I have to make my structures and functions in a .h header file.

I've created my structure but cannot use any of the variables within it as whenever I call it it highlights the structure name and tells me its not defined even though it clearly is in my structure and doesn't highlight or give me any syntax errors.

#include <stdio.h>

typedef struct test1 {
    int array1[3];
    int array2[3];
};

int main(void) {
    scanf_s(" %d %d", &test1.array1[1], &test1.array2[1]);

}

I have tried using typedef with and without and its the same result. if I create individual variables outside the structure I get no issues so i believe its some issue with how I'm creating my structures but I don't know what the issue is.

CodePudding user response：

The use of typedef makes me think that you actually want to define a type named test1. Move the name to after the struct:

#include <stdio.h>

typedef struct {
    int array1[3];
    int array2[3];
} test1;            // now a name you can use

You then need to create an instance of test1 to be able to use it with scanf_s:

int main(void) {
    test1 t1;      // `t1` is now a `test1` instance

    scanf_s(" %d %d", &t1.array1[1], &t1.array2[1]);
//                     ^^             ^^
}

CodePudding user response：

You declared type specifier struct test1 (and moreover the typedef declaration does not even declare a typedef name for the type specifier struct test1)

typedef struct test1 {
    int array1[3];
    int array2[3];
};

But the call of scanf_s

scanf_s(" %d %d", &test1.array1[1], &test1.array2[1]);

expects objects. test1 is not an object. This name is not even declared.

You could write for example

struct test1 test1;
scanf_s(" %d %d", &test1.array1[1], &test1.array2[1]);