Linux--进程间通信（二）-命名管道（pipe）通信

• server.c
• client.c
• pipelib.h
• 编译命令：gcc -o server server.c pipelib.h
• 编译命令：gcc -o client client.c pipelib.h
• 运行命令：./server
• 运行命令：./client.c

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server.c

#include "pipelib.h"#include <stdio.h>#include <string.h>#include <stdlib.h>int main() {        int server_fifo_fd;        int client_fifo_fd;        int res;        char client_fifo_name[NAME_SIZE];        message msg;        char *p;        if ( mkfifo(SERVER_FIFO_NAME, 0777) == -1) {//创建服务器从客户端接收消息的管道文件                fprintf(stderr, "Sorry,create server fifo failure!\n" );                return -1;        }        server_fifo_fd = open(SERVER_FIFO_NAME, O_RDONLY);//以读的方式打开服务器管道        if (server_fifo_fd == -1) {                fprintf(stderr, "Sorry server fifo open failure!\n" );                return -1;        }        sleep(5);        while ( res = read(server_fifo_fd, &msg, sizeof(msg)) > 0) {                p = msg.data;                while (*p){                        *p = toupper(*p);/*转换为大写字母*/                        ++p;                }                sprintf(client_fifo_name, CLIENT_FIFO_NAME, msg.client_pid);                client_fifo_fd = open(CLIENT_FIFO_NAME, O_WRONLY);/*以写的方式打开客户端通道*/                if (client_fifo_fd == -1){                        fprintf(stderr, "Sorry,client fifo open failure!\n" );                        return -1;                }                write(client_fifo_fd, &msg, sizeof(msg));/*将消息通过client的管道发送给客户端*/                close(client_fifo_fd);        }        close(server_fifo_fd);        unlink(SERVER_FIFO_NAME);        exit(EXIT_SUCCESS);}

client.c

#include "pipelib.h"#include <stdio.h>#include <string.h>#include <stdlib.h>int main(){        int server_fifo_fd;        int client_fifo_fd;        int res;        char client_fifo_name[NAME_SIZE];        message msg;        msg.client_pid = getpid();        sprintf(client_fifo_name, CLIENT_FIFO_NAME, msg.client_pid);/*将客户进程的pid写入结构体中*/        if ( mkfifo(client_fifo_name, 0777) == -1) {/*创建向服务器发送消息的管道文件*/                fprintf(stderr, "Sorry,create client fifo failure!\n" );                return -1;        }        server_fifo_fd = open(SERVER_FIFO_NAME, O_WRONLY);/*以写的方式打开服务器通道*/        if (server_fifo_fd == -1) {                fprintf(stderr, "Sorry ,open server fifo failure!\n" );                return -1;        }        sprintf(msg.data, "Hello from: %d",msg.client_pid);/*向服务器进程发送Hello from PID信息*/        printf("%d sent %s\n",msg.client_pid, msg.data );        write(server_fifo_fd, &msg, sizeof(msg));        client_fifo_fd = open(client_fifo_name, O_RDONLY);/*以读的方式打开客户端通道*/        if (client_fifo_fd == -1) {                fprintf(stderr, "Sorry ,client fifo open failure!\n");                return -1;        }        res = read(client_fifo_fd, &msg, sizeof(msg));/*从服务器接收数据*/        if (res > 0) {                printf("received:%s\n", msg.data);        }        close(client_fifo_fd);        close(server_fifo_fd);        unlink(client_fifo_name);        return 0;}

pipelib.h

#include <string.h>#include <fcntl.h>#include <limits.h>#include <sys/types.h>#include <sys/stat.h>#define SERVER_FIFO_NAME "/web/liefyuan/study/android/server_fifo"#define CLIENT_FIFO_NAME "/web/liefyuan/study/android/client_fifo"#define BUFFER_SIZE PIPE_BUF#define MESSAGE_SIZE 256#define NAME_SIZE 256typedef struct message{        pid_t client_pid;        char data[MESSAGE_SIZE + 1];}message;