Linux進程通信之文件

父子進程共享打開的文件描述符------使用文件完成進程間通信.

/*** fork_share_fd.c***/
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <fcntl.h>
#include <sys/wait.h>int main(void)
{int fd1, fd2; pid_t pid;char buf[1024];char *str = "---------test for shared fd in parent child process-----\n";pid = fork();if (pid < 0) {perror("fork error");exit(1);} else if (pid == 0) {fd1 = open("test.txt", O_RDWR);if (fd1 < 0) {perror("open error");exit(1);}write(fd1, str, strlen(str));printf("child wrote over...\n");} else {fd2 = open("test.txt", O_RDWR);if (fd2 < 0) {perror("open error");exit(1);}sleep(1);                   //保證子進程寫入數據int len = read(fd2, buf, sizeof(buf));write(STDOUT_FILENO, buf, len);wait(NULL);}return 0;
}

運行結果：

ubuntu1604@ubuntu:~/wangqinghe/linux/20190806$ ./fork_share_fd

child wrote over...

---------test for shared fd in parent child process-----