/*
 * 成功测试时的输出：
 * "  Write to pipe successfully."
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <assert.h>

static int fd[2];

void test_pipe(void){
    int cpid;
    char buf[128] = {0};
    int ret = pipe2(fd, 0);
    assert(ret != -1);
    const char *data = "  Write to pipe successfully.\n";
    cpid = fork();
    printf("cpid: %d\n", cpid);
    if(cpid > 0){
        close(fd[1]);
        while(read(fd[0], buf, 1) > 0)
                write(STDOUT_FILENO, buf, 1);
        write(STDOUT_FILENO, "\n", 1);
        close(fd[0]);
        wait(NULL);
    }else{
        close(fd[0]);
        write(fd[1], data, strlen(data));
        close(fd[1]);
        exit(0);
    }
}

int main(void){
    test_pipe();
    return 0;
}