如何將結構添加到結構數組的結尾？

Question

我有一個動態分配的結構數組。我想添加新的結構到數組的末尾。

的結構定義爲

struct book 
{ 
    char *id; 
    char *bookName; 
    char *authorName; 
    char *numOfPages; 
    char *publishingYear; 
    char *category; 
} typedef t_book; 

定義爲

t_book* books= (t_book*)malloc(4*sizeof(t_book)); 

Answer 1

重新分配存儲器與realloc()

size_t new_book_count = book_count + 1; 
//        size of 1 book * book count 
void *newbooks = realloc(books, sizeof *books * new_book_count); 
// Successful ? 
if (newbooks == NULL) { 
    perror("Out of memory"); 
    return error; 
} 
books = newbooks; 
// copy in new structure 
books[book_count] = new_struct; 
book_count = new_book_count; 

Answer 2

陣列這樣做

t_book* books; 
books = malloc(4 * sizeof *books); //Preferred way to do malloc 
//At this point you want to add one in the end 
t_book* bookstemp=realloc(books,5 * sizeof *books); 
// temporary variable for the case where realloc fails not to loose data 
if(bookstemp){ 
    printf("Realloc succeeded\n"); 
    books=bookstemp; 
} 
else 
    printf("Realloc failed\n");