socket编程API总结

一、 代码 注释

#include <sys/types.h>#include <sys/socket.h>#include <stdio.h>#include <stdlib.h>#include <errno.h>#include <string.h>#include <unistd.h>#include <netinet/in.h>#define SERVPORT 3333#define BACKLOG 10#define MAX_CONNECTED_NO 10#define MAXDATASIZE 5 int main(){        struct sockaddr_in server_sockaddr,client_sockaddr;        int sin_size,recvbytes;        int sockfd,client_fd;        char buf[MAXDATASIZE];        if((sockfd = socket(AF_INET,SOCK_STREAM,0))==-1){                perror("socket");                exit(1);        }        printf("socket success!,sockfd=%d\n",sockfd);        server_sockaddr.sin_family=AF_INET;        server_sockaddr.sin_port=htons(SERVPORT);        server_sockaddr.sin_addr.s_addr=INADDR_ANY;        bzero(&(server_sockaddr.sin_zero),8);        if(bind(sockfd,(struct sockaddr *)&server_sockaddr,sizeof(struct sockaddr))==-1){                perror("bind");                exit(1);        }        printf("bind success!\n");        if(listen(sockfd,BACKLOG)==-1){                perror("listen");                exit(1);        }        printf("listening....\n");        if((client_fd=accept(sockfd,(struct sockaddr *)&client_sockaddr,&sin_size))==-1){                perror("accept");                exit(1);        }        if((recvbytes=recv(client_fd,buf,MAXDATASIZE,0))==-1){                perror("recv");                exit(1);        }        printf("received a connection :%s\n",buf);        close(sockfd);}