使用内存映射文件（mmap）

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34

#include <stdio.h> #include <sys/mman.h> #include <fcntl.h> #include <unistd.h>   int main() {     int fd = open("/dev/zero", O_RDWR);     if (fd == -1) {         perror("open");         return 1;     }       size_t length = 4096; // 4KB     void *ptr = mmap(NULL, length, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);     if (ptr == MAP_FAILED) {         perror("mmap");         close(fd);         return 1;     }       // 使用映射的内存     char *data = (char *)ptr;     data[0] = 'H';     data[1] = 'i';     data[2] = '\0';     printf("%s\n", data);       // 释放映射的内存     if (munmap(ptr, length) == -1) {         perror("munmap");     }     close(fd);     return 0; }

　　内存映射代码保存一个