c - Difference between typedef struct and struct? -

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i know basic difference between them have doubt in particular situation following:

struct books{     int id;     char* title;       }book;  book.id=9;    // valid;

but in case of typedef :

typedef struct books{   int id;   char*title; }book; book.id=9;    //it not valid have book b1; b1.id=9 valid

what going on here can u tell me?

in first case, creating object of type struct books named book.

in second, defining alias book type struct books. book not object type name.


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