#include <stdio.h>#include <sys/types.h>#include <sys/socket.h>#include <sys/un.h>#define UNIX_DOMAIN "unix.domain"int main(void){	int com_fd;	int ret;	char snd_buf[1024];	int i;	static struct sockaddr_un srv_addr;	static struct sockaddr_un clt_addr;	char clt_file[]="xxxx";	srv_addr.sun_family=AF_UNIX;	strcpy(srv_addr.sun_path,UNIX_DOMAIN);		com_fd=socket(PF_UNIX,SOCK_DGRAM,0);	if(com_fd<0){		perror("cannot create communication socket");		return 1;	}			mkstemp(clt_file);		clt_addr.sun_family=AF_UNIX;	strcpy(clt_addr.sun_path,clt_file);	unlink(clt_file);		ret=bind(com_fd,(struct sockaddr*)&clt_addr,sizeof(clt_addr.sun_family)+strlen(clt_addr.sun_path));        if(ret==-1){                perror("cannot bind server socket");                return 1;        }	memset(snd_buf,0,1024);	sprintf(snd_buf,"%ld : message from client",(long)getpid());	for(i=0;i<4;i++){		sleep(1);		int num=sendto(com_fd,snd_buf,sizeof(snd_buf),0,(struct sockaddr*)&srv_addr,sizeof(struct sockaddr));		printf("send %d characters\n",num);		}	close(com_fd);	unlink(clt_file);	return 0;}