DragonOS/user/apps/c_unitest/test_mkfifo.c

#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

#define BUFFER_SIZE 256
#define PIPE_NAME "/bin/fifo"

int main() {
  pid_t pid;
  int pipe_fd;
  char buffer[BUFFER_SIZE];
  int bytes_read;
  int status;

  // 创建命名管道
  mkfifo(PIPE_NAME, 0666);

  // 创建子进程
  pid = fork();

  if (pid < 0) {
    fprintf(stderr, "Fork failed\n");
    return 1;
  } else if (pid == 0) {
    // 子进程

    // 打开管道以供读取
    pipe_fd = open(PIPE_NAME, O_RDONLY);

    // 从管道中读取数据
    bytes_read = read(pipe_fd, buffer, BUFFER_SIZE);
    if (bytes_read > 0) {
      printf("Child process received message: %s\n", buffer);
    }

    // 关闭管道文件描述符
    close(pipe_fd);

    // 删除命名管道
    unlink(PIPE_NAME);

    exit(0);
  } else {
    // 父进程

    // 打开管道以供写入
    pipe_fd = open(PIPE_NAME, O_WRONLY);

    // 向管道写入数据
    const char *message = "Hello from parent process";
    write(pipe_fd, message, strlen(message) + 1);

    // 关闭管道文件描述符
    close(pipe_fd);

    // 等待子进程结束
    waitpid(pid, &status, 0);

    if (WIFEXITED(status)) {
      printf("Child process exited with status: %d\n", WEXITSTATUS(status));
    }
  }

  return 0;
}