一、有名管道重点截图： ![图片描述](https://dn-simplecloud.shiyanlou.com/uid/426006/1497855593106.png-wm) ![图片描述](https://dn-simplecloud.shiyanlou.com/uid/426006/1497855594521.png-wm) ![图片描述](https://dn-simplecloud.shiyanlou.com/uid/426006/1497855595511.png-wm) 代码部分 fifo_write.c #include #include #include #include #include #include #include #include #define MYFIFO "/tmp/myfifo" //有名管道的文件名 #define MAX_BUFFER_SIZE PIPE_BUF //定义在 limits.h 中 int main(int argc, char * argv[]) { int fd; char buff[MAX_BUFFER_SIZE]; int nwrite; if(argc <= 1){ //判断是否有参数 printf("Usage: ./fifo_write string\n"); exit(1); } sscanf(argv[1], "%s", buff); //保存已经输入参数 fd = open(MYFIFO, O_WRONLY); //以只写阻塞方式打开 FIFO 管道 if (fd == -1){ //管道是否打开成功 printf("Open fifo file error\n"); exit(1); } if ((nwrite = write(fd, buff, MAX_BUFFER_SIZE)) > 0){ printf("Write '%s' to FIFO\n", buff); } close(fd); exit(0); } fifo_read.c #include #include #include #include #include #include #include #include #define MYFIFO "/tmp/myfifo" // 有名管道的文件名 #define MAX_BUFFER_SIZE PIPE_BUF // 定义在 limits.h 中 int main() { char buff[MAX_BUFFER_SIZE]; int fd; int nread; if (access(MYFIFO, F_OK) == -1){ // 判断有名管道是否已存在 if ((mkfifo(MYFIFO, 0666) < 0) && (errno != EEXIST)){ printf("Cannot create fifo file\n"); exit(1); } } fd = open(MYFIFO, O_RDONLY); // 以只读阻塞方式打开有名管道 if (fd == -1){ // 判断管道是否打开完成 printf("Open fifo file error\n"); exit(1); } while (1){ // 读取管道信息 memset(buff, 0, sizeof(buff)); if ((nread = read(fd, buff, MAX_BUFFER_SIZE)) > 0){ printf("Read '%s' from FIFO\n", buff); } } close(fd); exit(0); } 二、消息队列重点截图 ![图片描述](https://dn-simplecloud.shiyanlou.com/uid/426006/1497856048926.png-wm) msgsnd.c #include #include #include #include #include #include #include #define BUFFER_SIZE 512 struct message { long msg_type; char msg_text[BUFFER_SIZE]; }; int main() { int qid; key_t key; struct message msg; if ((key = ftok(".", 'a')) == -1){ // 判断key是否生成成功 perror("ftok"); exit(1); } // 如果key对应的消息队列不存在，创建消息队列 if ((qid = msgget(key, IPC_CREAT|0666)) == -1){ // 判断消息队列是否生成成功 perror("msgget"); exit(1); } printf("Open queue %d\n",qid); while(1){ // 添加消息到消息队列 printf("Enter some message to the queue:"); if ((fgets(msg.msg_text, BUFFER_SIZE, stdin)) == NULL){ // 没有读取到数据，读取错误返回NULL puts("no message"); exit(1); } msg.msg_type = getpid(); if ((msgsnd(qid, &msg, strlen(msg.msg_text), 0)) < 0){ // 判断是否添加成功成功返回0失败返回-1 perror("message posted"); exit(1); } if (strncmp(msg.msg_text, "quit", 4) == 0){ break; } } exit(0); } msgrcv.c #include #include #include #include #include #include #include #define BUFFER_SIZE 512 struct message { long msg_type; char msg_text[BUFFER_SIZE]; }; int main() { int qid; key_t key; struct message msg; if ((key = ftok(".", 'a')) == -1){ // 判断key是否生成成功 perror("ftok"); exit(1); } // 如果key消息队列不存在，创建消息队列 if ((qid = msgget(key, IPC_CREAT|0666)) == -1) { // 消息队列是否生成成功 perror("msgget"); exit(1); } printf("Open queue %d\n", qid); do{ memset(msg.msg_text, 0, BUFFER_SIZE); if (msgrcv(qid, (void*)&msg, BUFFER_SIZE, 0, 0) < 0){ // 判断是否读取成功，成功返回字节数，失败返回-1 perror("msgrcv"); exit(1); } printf("The message from process %d : %s", msg.msg_type, msg.msg_text); } while(strncmp(msg.msg_text, "quit", 4)); if ((msgctl(qid, IPC_RMID, NULL)) < 0){ // 判断是否成功成功返回0失败返回-1 perror("msgctl"); exit(1); } exit(0); }

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