#include <sys/time.h>

// return -1 on error, 0 on timeout after sec seconds:
int readTimeout(int fd, double sec)  // 
{
  fd_set rset;
  struct timeval tv;
  FD_ZERO(&rset);
  FD_SET(fd,&rset);
  tv.tv_sec = (long) sec;
  tv.tv_usec = (long)((sec - (double)(tv.tv_sec))*1000000.0);
  return (select(fd+1,&rset,NULL,NULL,&tv));
} // readTimeout