MULTIPLEXING USING SOCKET OPTION

["Lakshmi Gopinath" <lakbala@xxxxxxxx>]

/* Program using socket option to multiplex */

#include<stdlib.h>
#include<netinet/in.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<arpa/inet.h>
#include<sys/select.h>
#include<sys/time.h>
#include<errno.h>
#define max(a,b) ((a) > (b) ? (a) : (b))
#define PORTA 6000
#define PORTB 8000

struct sockaddr_in  serv_addr1,serv_addr2;
int main()
{
  int sockfd1,sockfd2,count=0,length=0,maxfd1;
  char buff1[128],buff2[128];
  struct timeval *test = (struct timeval *)malloc(sizeof(struct timeval));
  struct timeval time;
  socklen_t *optlen = (socklen_t *)malloc(sizeof(struct timeval));
  time.tv_sec = 2000;
  time.tv_usec = 0;
  printf("reciever running\n");
  serv_addr1.sin_family=AF_INET;
  serv_addr1.sin_addr.s_addr=inet_addr("127.0.0.1");
  serv_addr1.sin_port=htons(PORTA);
  if((sockfd1=socket(AF_INET,SOCK_DGRAM,0))<0)
     write("I/O socket error\n");
  if((bind(sockfd1,(struct sockaddr *)&serv_addr1,sizeof(serv_addr1)))<0)
    printf("bind error\n");
  setsockopt(sockfd1,SOL_SOCKET,SO_RCVTIMEO,&time,sizeof(time));
  getsockopt(sockfd1,SOL_SOCKET,SO_RCVTIMEO,test,optlen);
  printf("\n sec = %d",test->tv_sec);
  printf("\n msec = %d",test->tv_usec);
  serv_addr2.sin_family=AF_INET;
  serv_addr2.sin_addr.s_addr=inet_addr("127.0.0.1");
  serv_addr2.sin_port=htons(PORTB);
  if((sockfd2=socket(AF_INET,SOCK_DGRAM,0))<0)
     write("I/O socket error\n");
  if((bind(sockfd2,(struct sockaddr *)&serv_addr2,sizeof(serv_addr2)))<0)
    printf("bind error\n");
  setsockopt(sockfd2,SOL_SOCKET,SO_RCVTIMEO,&time,sizeof(time));
  printf("\n ok");
  for(;;)
  {
      count = recvfrom(sockfd1,(char *)buff1,sizeof(buff1),0,NULL,NULL);
       if(count < 0)
        {
          if (errno == EWOULDBLOCK)
            {
              printf("\n blcok");
              continue;
            }
          else
             printf("\n recvfrom error\n");
         }
        else
           printf("\n %s ",buff1);
       count = recvfrom(sockfd2,(char *)buff2,sizeof(buff2),0,NULL,NULL);
       if(count < 0)
          {
            if (errno == EWOULDBLOCK)
               continue;
            else
              printf("\n recvfrom error \n");
           }
       else
           printf("\n %s ",buff2);
     }
    
}