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Select() never timeouts

I got this code in my program. I expected the select to timeout but it never timeouts.

here it is. Can you please check if there is something wrong with the code

Code:

int

check_sockets(int sock1_fd, int sock2_fd)

{



    struct timeval tv;

    fd_set fds;

    int retval;

    int i;

    int fd_max;

    rv = 0;



    if ( sock1_fd >  sock2_fd)

        fd_max = sock1_fd;

    else

        fd_max = sock2_fd;

    

    

    while (running) {

        

        tv.tv_sec = 2;

        tv.tv_usec = 0;



        FD_ZERO(&fds);

        

        FD_SET(sock1_fd, &fds);

        FD_SET(sock2_fd, &fds);



  

        i = select( fd_max + 1, &fds, NULL, NULL, &tv);



        

        if (running == 0)

            break;



        if (i == 0)

        {  

            /*handle timeout*/

            continue;

        }

        else

        {

            /* data is ready on socket1 */

            if (FD_ISSET(sock1_fd, &fds)) {

                /*check socket 1 for data*/

            }

            /* data is ready on socket2 */

            if 

            (FD_ISSET(sock2_fd, &fds)) {

                /*check socket 2 for data*/

            } 

        }

    }



    return retval;

}

socket1 is a normal udp socket. and socket 2 is a raw socket.

Are there any instances where I should set the socket as non-blocking before using select?

Quote:

Originally Posted by PinoyAko (Post 4357967)

I got this code in my program. I expected the select to timeout but it never timeouts.

Based on the code you submitted, I find that hard to believe. Here... try a simpler program:

Code:

#include <sys/select.h>

#include <stdio.h>

#include <assert.h>



void timer(int secs, int usecs)

{

  struct timeval tv;



  tv.tv_sec  = secs;

  tv.tv_usec = usecs;



  int i = select(0, NULL, NULL, NULL, &tv);



  assert(i == 0);

  printf("timeout.\n");

}



int main()

{

  timer(2, 0);

  return 0;

}

Quote:

Originally Posted by PinoyAko (Post 4357967)

socket1 is a normal udp socket. and socket 2 is a raw socket.

Are there any instances where I should set the socket as non-blocking before using select?

Setting a socket to non-blocking will not have any bearing on select(). The select() function merely tells you when there is activity on a particular descriptor.

Why are you using a raw socket (and what flavor, tcp or udp)??

Oooppss my bad. After checking all the variables included, I found out that the value of timeout was actually 2000 (I actually modified posted code the number 2 was actually a defined value which was not updated on the server where I am compiling the change was only done on my local computer :) I guess I should diff every files before compiling to check for inconsistencies.

As for the raw socket it is actually an ICMP socket. I will be sending some icmp requests.

Thank you