linux兩個服務消息隊列通訊

②消息隊列通訊

 

send.c

 

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>

#define MAX_TEXT 512

 

/*用於消息收發的結構體--my_msg_type：消息類型，some_text：消息正文*/
struct my_msg_st
{
 long int my_msg_type;
 char some_text[MAX_TEXT];
};

 

int main()
{
 int running = 1;//程序運行標識符
 struct my_msg_st some_data;
 int msgid;//消息隊列標識符
 char buffer[BUFSIZ];


 /*建立與接受者相同的消息隊列*/
 msgid = msgget((key_t)1234, 0666 | IPC_CREAT);
 if (msgid == -1) 
 {
  fprintf(stderr, "msgget failed with error: %d/n", errno);
  exit(EXIT_FAILURE);
 }

 

 /*向消息隊列中發送消息*/
 while(running) 
 {
  printf("Enter some text: ");
  fgets(buffer, BUFSIZ, stdin);
  some_data.my_msg_type = 1;
  strcpy(some_data.some_text, buffer);
  if (msgsnd(msgid, (void *)&some_data, MAX_TEXT, 0) == -1) 
  {
   fprintf(stderr, "msgsnd failed/n");
   exit(EXIT_FAILURE);
  }
  if (strncmp(buffer, "end", 3) == 0) 
  {
   running = 0;
  }
 }
 exit(EXIT_SUCCESS);
}

 

receive.c

 

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>

 

/*用於消息收發的結構體--my_msg_type：消息類型，some_text：消息正文*/
struct my_msg_st
{
 long int my_msg_type;
 char some_text[BUFSIZ];
};

 

int main()
{
 int running = 1;//程序運行標識符
 int msgid; //消息隊列標識符
 struct my_msg_st some_data; 
 long int msg_to_receive = 0;//接收消息的類型--0表示msgid隊列上的第一個消息

 

 /*建立消息隊列*/
 msgid = msgget((key_t)1234, 0666 | IPC_CREAT);
 if (msgid == -1) 
 {
  fprintf(stderr, "msgget failed with error: %d/n", errno);
  exit(EXIT_FAILURE);
 }

 

 /*接收消息*/
 while(running) 
 {
  if (msgrcv(msgid, (void *)&some_data, BUFSIZ,msg_to_receive, 0) == -1) 
  {
   fprintf(stderr, "msgrcv failed with error: %d/n", errno);
   exit(EXIT_FAILURE);
  }
  printf("You wrote: %s", some_data.some_text);
  if (strncmp(some_data.some_text, "end", 3) == 0) 
  {
   running = 0;
  }
 }

 

 /*刪除消息隊列*/
 if (msgctl(msgid, IPC_RMID, 0) == -1) 
 {
  fprintf(stderr, "msgctl(IPC_RMID) failed/n");
  exit(EXIT_FAILURE);
 }
 exit(EXIT_SUCCESS);
}