### malloc分配內存 - malloc用來分配空間，然后返回一個指針，指向堆上新分配的空間 - 使用malloc時需要引入頭文件stdlib.h - malloc需要知道數據類型所占的字節，通常配合sizeof使用，例如： swServer *p = malloc(sizeof(struct swServer)); ```c #include <stdio.h> #include <stdlib.h> #include <malloc.h> #include <string.h> typedef struct island { char *name; struct island *next; } island; void display(island *island) { for (; island != NULL; island = island->next) { printf("name: %s\n", island->name); } } island* create(char *name) { island *i = malloc(sizeof(island)); i->name = strdup(name); /* 記得要釋放strdup在堆上創建的空間 */ i->next = NULL; return i; } void release(island *start) { island *i = start; island *next = NULL; while (i != NULL) { next = i->next; free(i->name); /* 釋放strdup創建的name字段 */ free(i); i = next; } } int main() { island *start = NULL; island *i = NULL; island *next = NULL; char name[80]; for (; fgets(name, 80, stdin) != NULL; i = next) { next = create(name); if (start == NULL) { start = next; } if (i != NULL) { i->next = next; } } display(start); release(start); } ```