[a1369209993]

  > for (int fd = open(...); fd != -1; fd = -1) {

that doesn't correctly (or rather at all) handle the failure case. You should do (IIRC):

  #define LET(...) for(__VA_ARGS__,_tmp[0],*_once=_tmp; _once ;_once=0)
  /* ^^^ goes in a header file */
  LET(int fd = open())
    {
    if(fd == -1) { /* handle error, return or break */ }
    /* do stuff */
    }