tchtcpserd.c

通信程序

#include <stdio.h> 
#include <stdlib.h> 
#include <errno.h> 
#include <string.h> 
#include <sys/types.h> 
#include <netinet/in.h> 
#include <sys/socket.h> 
#include <sys/wait.h> 

#define MYPORT 3490    /* the port users will be connecting to */
#define BACKLOG 10     /* how many pending connections queue will hold */

main()
{
	int sockfd, new_fd;  /* listen on sock_fd, new connection on new_fd */
	struct sockaddr_in my_addr;    /* my address information */
	struct sockaddr_in their_addr; /* connector's address information */
	int sin_size;

	if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) 
	{
	    perror("socket error");
	    exit(1);
	}
	printf("socket sucess\n");

	my_addr.sin_family = AF_INET;         /* host byte order */
	my_addr.sin_port = htons(MYPORT);     /* short, network byte order */
	my_addr.sin_addr.s_addr = INADDR_ANY; /* auto-fill with my IP */
	bzero(&(my_addr.sin_zero), 8);        /* zero the rest of the struct */

	if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) == -1) 
	{
	    perror("bind error");
	    exit(1);
	}
	printf("bind sucess\n");

	if (listen(sockfd, BACKLOG) == -1) 
	{
	    perror("listen error");
	    exit(1);
	}
	printf("listen sucess\n");

	while(1) 
	{                  /* main accept() loop */
		sin_size = sizeof(struct sockaddr_in);
		if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size)) == -1) 
		{
			perror("accept error\n");
			continue;
		}
		printf("server: got connection from %s\n", inet_ntoa(their_addr.sin_addr));
		if (!fork()) 
		{        /* this is the child process */
			if (send(new_fd, "Hello, world!\n", 14, 0) == -1)
			perror("send error\n");
			close(new_fd);
			exit(0);
		}
		close(new_fd);  /* parent doesn't need this */
		while(waitpid(-1,NULL,WNOHANG) > 0); /* clean up child processes */
	}
}