udpdmain.c

DOS下的TCP/IP源代码,可以做参考.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <conio.h>
#include <dos.h>
#include <time.h>
#include <alloc.h>
#include "tcplib.h"
//=====================================================================
UDPSocket udps;
char udpbuf[520];
int hostport;
int udpl=0;
//=====================================================================
int checkudp(void)
{int len;
 udp_kernal(NULL);
 if (udpl==0)
    {listen_udp(udps,hostport);
     udpl=1;
    }
 if (!peer_udp_data(udps)) return 0;
 len=udp_recv(udps,udpbuf,512);
 udpbuf[len]=0;
 close_udp((UDPSocket)udps);
 udpl=0;
 return 1;
}

//=====================================================================
int main()
{int rc,sum=0;
 char buf[128];

 printf("\nUDP SERVER 8888\n");

 init_tcplib();
 hostport=8888;
 udps=new_udpsocket();
 listen_udp(udps,hostport);
 udpl=1;

 while(!kbhit())
   {rc=checkudp();
    if (rc>0)
     {sum++;
      printf("Received %d: %s\n",sum,udpbuf);
      sprintf(buf,"%d: Hi,How are you ?\r\n",sum);
      udp_send_back(udps,hostport,buf,strlen(buf));
     }
   }

 release_udpsocket(udps);

 return(0);
}