socket.h

linux下的人机对话编程

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include<stdio.h>
#include<string.h>
	char check_error[16348]={};
	struct sockaddr_in pin;
	struct hostent *server_host_name;
int socket_com(char *host_name,int port, char *str)
{	
	char buf[8192]={};
	char port_exchange[10]={};
        int socket_descriptor;
        int errorcount1=1;
        int errorcount2=1;
        int errorcount3=1;
        int errorcount4=1;
        int errorcount5=1;
        int export_flag=0;
//resolving the host name
	while(errorcount1<=3)
	{
	if((server_host_name=gethostbyname(host_name))==0)
		errorcount1++;
        else break;
	}
	if(errorcount1==4)
	{
	strcpy(check_error,"Host_name:");
	strcat(check_error,host_name);
	strcat(check_error," Port:");
	sprintf(port_exchange,"%d",port);
	strcat(check_error,port_exchange);
	strcat(check_error,": Error resolving local host\n");
	return -1;
        }
 //init the port now
	bzero(&pin,sizeof(pin));
	pin.sin_family=AF_INET;
	pin.sin_addr.s_addr=htonl(INADDR_ANY);
	pin.sin_addr.s_addr=((struct in_addr*)(server_host_name->h_addr))->s_addr;
        pin.sin_port=htons(port);
//create socket
	while(errorcount2<=3)
	{
	if((socket_descriptor=socket(AF_INET,SOCK_STREAM,0))==-1)
	errorcount2++;
        else  break;
        }
	if(errorcount2==4)
	{
	strcpy(check_error,"Host_name:");
	strcat(check_error,host_name);
	strcat(check_error," Port:");
	sprintf(port_exchange,"%d",port);
        strcat(check_error,port_exchange);
        strcat(check_error,": Error create socket\n");
	return -1;
        }
//check connect
	while(errorcount3<=3)
	{
	if(connect(socket_descriptor,(void*)&pin,sizeof(pin))==-1)
	errorcount3++;
      	else  break;
        }
        if(errorcount3==4)
        {
	strcpy(check_error,"Host_name:");
	strcat(check_error,host_name);
	strcat(check_error," Port:");
	sprintf(port_exchange,"%d",port);
        strcat(check_error,port_exchange);
        strcat(check_error,": Error connecting socket\n");
	return -1;
        }
//check send
	while(errorcount4<=3)
        {
	if(send(socket_descriptor,str,strlen(str),0)==-1)
        errorcount4++;
        else  break;
        }
        if(errorcount4==4)
        {
	strcpy(check_error,"Host_name:");
	strcat(check_error,host_name);
	strcat(check_error," Port:");
	sprintf(port_exchange,"%d",port);
        strcat(check_error,port_exchange);
        strcat(check_error,": Error in send\n");
	return -1;
        }
//check receive        
     	while(errorcount5<=3)
        {
        if(recv(socket_descriptor, buf, 8192, 0)==-1)
        errorcount5++;
        else  break;
        }
       if(errorcount5==4)
	{
	strcpy(check_error,"Host_name:");
	strcat(check_error,host_name);
	strcat(check_error," Port:");
	sprintf(port_exchange,"%d",port);
        strcat(check_error,port_exchange);
        strcat(check_error,": Error in receive\n");
	return -1;
        }
//check result
   	strcpy(check_error,buf);
        close(socket_descriptor);
   return 0;

}