进程间通信：本地聊天程序

#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <string.h>
const int SIZE=128;
//gcc a.c -o a
//./a 用户名 写管道名 读管道名
int main(int argc, char **argv) {
    if(argc != 4)
    {
        printf("参数错误！");
        exit(1);
    }
    char *name = argv[1],
          *write_pipe = argv[2],
          *read_pipe = argv[3]; 
//子进程写
    if(0 == fork())
    {
        char buf[SIZE];
        int write_fd = -1;

        // 创建写管道
        if(-1 == access(write_pipe, F_OK))
            if(-1 == (write_fd = mkfifo(write_pipe,0644)))
                perror("mkfifo");
        //打开写管道
        if(-1 == (write_fd = open(write_pipe, O_WRONLY)))
            perror("open");
        while(1)
        {
            memset(buf, 0, SIZE);
            fgets(buf, SIZE, stdin);
            write(write_fd, name, strlen(name));
            write(write_fd, ":", 1);
            write(write_fd, buf, SIZE);
        }
        exit(0);
    }

//父进程读
    char buf[SIZE];
    int read_fd = -1;

    // //创建读管道
    if(-1 == access(read_pipe, F_OK))
        if(-1 == (read_fd = mkfifo(read_pipe,0644)))
            perror("mkfifo");
    //打开读管道
    if(-1 == (read_fd = open(read_pipe, O_RDONLY)))
        perror("open");

    while(1)
    {
        memset(buf, 0, SIZE);
        if(read(read_fd, buf, SIZE) <= 0) 
        {
            perror("read");
            break;
        }
        printf("\n%s",buf);
    }
    return 0;
}