运用消息队列进行进程间通信

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/* * ===================================================================================== * * Filename: message_send.c * * Description: * * Version: 1.0 * Created: 2012年03月11日 21时33分45秒 * Revision: none * Compiler: gcc * * Author: MaZheng (blog.youkuaiyun.com/mazheng1989), mazheng19891019@gmail.com * Company: Dalian University Of Technology * * ===================================================================================== */ #include <sys/types.h> #include <sys/ipc.h> #include <stdlib.h> #include <sys/msg.h> #include <stdio.h> #include <string.h> #define MSGSZ 128 /* * Declare the message structure. */ typedef struct msgbuf { long mtype; char mtext[MSGSZ]; } message_buf; int main() { int msqid; int msgflg = IPC_CREAT | 0666; key_t key; message_buf sbuf; size_t buf_length; /* * Get the message queue id for the * "name" 1234, which was created by * the server. */ key = 1234; (void) fprintf(stderr, "\nmsgget: Calling msgget(%#lx,\ %#o)\n", key, msgflg); if ((msqid = msgget(key, msgflg )) < 0) { perror("msgget"); exit(1); } else (void) fprintf(stderr,"msgget: msgget succeeded: msqid = %d\n", msqid); /* * We'll send message type 1 */ sbuf.mtype = 1; (void) fprintf(stderr,"msgget: msgget succeeded: msqid = %d\n", msqid); (void) strcpy(sbuf.mtext, "Did you get this?"); (void) fprintf(stderr,"msgget: msgget succeeded: msqid = %d\n", msqid); buf_length = strlen(sbuf.mtext) + 1 ; /* * Send a message. */ if (msgsnd(msqid, &sbuf, buf_length, IPC_NOWAIT) < 0) { printf ("%d, %d, %s, %d\n", msqid, sbuf.mtype, sbuf.mtext, buf_length); perror("msgsnd"); exit(1); } else printf("Message: \"%s\" Sent\n", sbuf.mtext); exit(0); }
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/* * ===================================================================================== * * Filename: message_rec.c * * Description: * * Version: 1.0 * Created: 2012年03月11日 21时36分28秒 * Revision: none * Compiler: gcc * * Author: MaZheng (blog.youkuaiyun.com/mazheng1989), mazheng19891019@gmail.com * Company: Dalian University Of Technology * * ===================================================================================== */ #include <sys/types.h> #include <sys/ipc.h> #include <stdlib.h> #include <sys/msg.h> #include <stdio.h> #define MSGSZ 128 /* * Declare the message structure. */ typedef struct msgbuf { long mtype; char mtext[MSGSZ]; } message_buf; int main() { int msqid; key_t key; message_buf rbuf; /* * Get the message queue id for the * "name" 1234, which was created by * the server. */ key = 1234; if ((msqid = msgget(key, 0666)) < 0) { perror("msgget"); exit(1); } /* * Receive an answer of message type 1. */ if (msgrcv(msqid, &rbuf, MSGSZ, 1, 0) < 0) { perror("msgrcv"); exit(1); } /* * Print the answer. */ printf("%s\n", rbuf.mtext); exit(0); }