int file_wd_setexe(const char *zFilename, int onoff){
  int rc = 0;
#if !defined(_WIN32)
  struct stat buf;
  if( fossil_stat(zFilename, &buf, 1)!=0 || S_ISLNK(buf.st_mode) ) return 0;
  if( onoff ){
    int targetMode = (buf.st_mode & 0444)>>2;
    if( (buf.st_mode & 0100) == 0 ){
      chmod(zFilename, buf.st_mode | targetMode);
      rc = 1;
    }
  }else{
    if( (buf.st_mode & 0100) != 0 ){
      chmod(zFilename, buf.st_mode & ~0111);
      rc = 1;
    }
  }
#endif /* _WIN32 */
  return rc;
}