Impersonate server and client using message queuing

 Use message queuing to simulate server and client 
 client 1	 Send a message to the server , The sent message carries the identity of the message receiver 
 client 2	 Send a message to the server , The sent message carries the identity of the message receiver 
 Server side :	 receive messages , According to the message receiver ID in the message , Forward to the corresponding message receiver .

// Server side
server.c

#include "myhead.h"

typedef struct msgbuf 
{
     
	long mtype;      //  Identification of the message  
	char mtext[100]; //  The body of the message  
}MSG;

int main(int argc, char const *argv[])
{
    
	if (argc != 2)
	{
    
		printf("%s  Message ID \n", argv[0]);
		return -1;
	}
	int msgid, key;
	key = ftok("./", 1);
	if (key == -1)
	{
    
		perror("ftok() failed!");
		return -1;
	}

	msgid =	msgget(key, IPC_CREAT | 0666);
	if (msgid == -1)
	{
    
		perror("msgget() failed!");
		return -1;
	}
	MSG msg;
	int mtype=atoi(argv[1]);
	while(1)
	{
    
		//bzero(msg.mtext, sizeof(msg.mtext));
		printf(" Enter the message to send Ser->Cli:");
		scanf("%s",msg.mtext);
		int ret = msgsnd(msgid, &msg, strlen(msg.mtext)+1, 0);
		if (ret == -1)
		{
    
			perror("msgsnd() failed!");
			return -1;
		}
		msgrcv(msgid,&msg,sizeof(msg), mtype,0);// Receive ID is mtype The news of 
		printf(" Messages received Cli->Ser: %s\n",msg.mtext);
	}
	msgctl(msgid,IPC_RMID,NULL);
	return 0;
}

// The end of the service
client.c

#include "myhead.h"

typedef struct msgbuf 
{
     
	long mtype;      //  Identification of the message  
	char mtext[100]; //  The body of the message  
}MSG;

int main(int argc, char const *argv[])
{
    
	if (argc != 2)
	{
    
		printf("%s  Message ID \n", argv[0]);
		return -1;
	}
	int msgid, key;
	key = ftok("./", 1);
	if (key == -1)
	{
    
		perror("ftok() failed!");
		return -1;
	}

	msgid =	msgget(key, IPC_CREAT | 0666);
	if (msgid == -1)
	{
    
		perror("msgget() failed!");
		return -1;
	}
	
	MSG msg;
	int mtype=atoi(argv[1]);
	while(1)
	{
    
		//bzero(msg.mtext, sizeof(msg.mtext));
		msgrcv(msgid, &msg, sizeof(msg), mtype, 0);// Receive ID is mtype The news of 
		printf(" Messages received Ser->Cli:%s\n",msg.mtext);

		printf(" Enter the message to send Cli->Ser: ");
		scanf("%s",msg.mtext);
		
		int ret = msgsnd(msgid, &msg, strlen(msg.mtext)+1, 0);
		if (ret == -1)
		{
    
			perror("msgsnd() failed!");
			return -1;
		}
		printf(" Message sent successfully \n");
	}

	return 0;
}