C : typedef struct name {…}; VS typedef struct{…} name;

Question

As the title says, I have this code:

    typedef struct Book{
        int id;
        char title[256];
        char summ         


        

Answer 1

Want to add by clarifying when you actually declare a variable.

struct foo {
   int a;
} my_foo;

defines foo and immediately declares a variable my_foo of the struct foo type, meaning you can use it like this my_foo.a = 5;

However, because typedef syntax follows typedef

typedef struct bar {
   int b;
} my_bar;

is not declaring a variable my_bar of type struct bar, my_bar.b = 5; is illegal. It is instead giving a new name to the struct bar type in the form of my_bar. You can now declare the struct bar type with my_bar like this:

my_bar some_bar;