parent.c

一个在linux实现进程通信的例子,使用socket技术,相信对想了解进程通信的人有用用途

#include <sys/wait.h>
#include <stdio.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#define PARENTPORT 2234
#define CHILDPORT 1234
#define MAXSOCKFD 10
#define NULL 0
struct msg
{
	int processid;
	char strmsg[100];
};

int main(void)
{
	int ChildId=0;
	int ParentId;
	//char *argv={"/bin/ls",".",(char *)0};
	//char *envp={"PATH=/bin",0};
	
	struct msg parentmsg;
	int sockfd;
	struct sockaddr_in addr;
	struct sockaddr_in remote_addr;
	int addr_len=sizeof(struct sockaddr_in);
	int remote_len=sizeof(struct sockaddr_in);
	char buffer[256];
	if((sockfd=socket(AF_INET,SOCK_DGRAM,0))<0)
	{
		perror("socket");
		exit(1);
	}
	//remote child
	bzero(&remote_addr,sizeof(remote_addr));
	remote_addr.sin_family=AF_INET;
	remote_addr.sin_port=htons(CHILDPORT);
	remote_addr.sin_addr.s_addr=htonl(INADDR_ANY);
	//local
	bzero(&addr,sizeof(addr));
	addr.sin_family=AF_INET;
	addr.sin_port=htons(PARENTPORT);
	addr.sin_addr.s_addr=htonl(INADDR_ANY);
	if(bind(sockfd,&addr,sizeof(addr))<0)
	{
		perror("connect");
		exit(1);
	}
	
	if(fork()==0)
	{
		printf("child is starting...\n");
		ChildId=getpid();
		execve("./child",NULL,NULL);
		printf("child is exiting...\n");
		exit(0);	
	}
	printf("process [%d]:parent in execution...\n",getpid());
	
	ParentId=getpid();
	while(1)
	{
		//send msg to child
		parentmsg.processid=ParentId;
		strcpy(parentmsg.strmsg,"hello child i am your parent");
		memcpy(buffer,&parentmsg,sizeof(struct msg));
		sendto(sockfd,buffer,256,0,&remote_addr,remote_len);
		sleep(1);
		//recv msg from child
		recvfrom(sockfd,buffer,sizeof(buffer),0,&remote_addr,&remote_len);
		memset(&parentmsg,0,sizeof(struct msg));
		memcpy(&parentmsg,buffer,sizeof(struct msg));
		printf("The child processid is %d,and the content is %s\n",parentmsg.processid,parentmsg.strmsg);
		sleep(1);
		
	}
	sleep(2);
	if(wait(NULL)>0)
		printf("process [%d]:parent detects terminating child \n",getpid());
	printf("process [%d]:parent terminating ... \n",getpid());
}