UNIX环境高级编程学习之第十五章进程间通信 – 通过半双工匿名管道实现父子进程通信

/* User:Lixiujie
 * Date:20100818
 * Desc:父子进程通过半双工匿名管道通信
 */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>

int main(void){
        pid_t pid;
        int pfd[2];
        int cfd[2];
        char szBuf[256];
        if (pipe(pfd) < 0){
                perror("pipe(pfd) failed!");
                exit(1);
        }
        if (pipe(cfd) < 0){
                perror("pipe(cfd) failed!");
                exit(1);
        }
        if ((pid = fork()) < 0){
                perror("fork() failed!");
                exit(1);
        }else if (pid > 0){ // parent
                close(cfd[0]); // colse child read
                close(pfd[1]); // colse parent write
                while (1){
                        memset(szBuf, 0x00, sizeof(szBuf));
                        strcpy(szBuf, "P: Hello world!");
                        write(cfd[1], szBuf, strlen(szBuf)+1);
                        memset(szBuf, 0x00, sizeof(szBuf));
                        read(pfd[0], szBuf, sizeof(szBuf) - 1);
                        printf("%s/n", szBuf);
                        sleep(1);
                }
        }else{ // child
                close(cfd[1]);
                close(pfd[0]);
                while (1){
                        memset(szBuf, 0x00, sizeof(szBuf));
                        read(cfd[0], szBuf, sizeof(szBuf) - 1);
                        printf("%s/n", szBuf);
                        memset(szBuf, 0x00, sizeof(szBuf));
                        strcpy(szBuf, "C: Hello world!");
                        write(pfd[1], szBuf, strlen(szBuf)+1);
                        sleep(1);
                }
        }
        return 0;
}