tools/ncb.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <unistd.h>
   4 #include <sys/socket.h>
   5 #include <netinet/in.h>
   6
   7 int main (int argc, char *argv[])
   8 {
   9         int s, len, o, port = 6666;
  10         char buf[512];
  11         struct sockaddr_in addr;
  12         socklen_t addr_len = sizeof addr;
  13
  14         if (argc > 1)
  15                 port = atoi (argv[1]);
  16
  17         s = socket (PF_INET, SOCK_DGRAM, IPPROTO_UDP);
  18
  19         o = 1;
  20         len = 4;
  21         setsockopt (3, SOL_SOCKET, SO_REUSEADDR, &o, len);
  22
  23         addr.sin_family = AF_INET;
  24         addr.sin_port = htons (port);
  25         addr.sin_addr.s_addr = INADDR_ANY;      /* receive broadcasts */
  26
  27         bind (s, (struct sockaddr *) &addr, sizeof addr);
  28
  29         for (;;) {
  30                 len = recvfrom (s, buf, sizeof buf, 0, (struct sockaddr *) &addr, &addr_len);
  31                 if (len < 0)
  32                         break;
  33                 if (write (1, buf, len) != len)
  34                         fprintf(stderr, "WARNING: serial characters dropped\n");
  35         }
  36
  37         return 0;
  38 }