Event->io does not accept GLOB refs

As I read the documentation, Event->io should accept a GLOB
reference as argument, but I cannot get this to work (it only works
with some glob references, e.g. ones created by IO::Handle):

   use Event;

   my $fh = do { local *GLOB };
   open $fh, "<", "/dev/null" or die;

   print "fileno: ", fileno $fh, "\n";
   print "asstring: $fh\n"; 

   Event->io(fd => $fh, cb => sub {});

This prints:

fileno: 4
asstring: *main::GLOB
Event: can't start '?? x.pl:12' because there is nothing to watch at x.pl line 12

Devel::Peek thinks this about the $fh:

SV = PVGV(0x81a79c0) at 0x811e5a8
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY,GMG,SMG,FAKE,pPOK,MULTI)
  IV = 0
  NV = 0
  MAGIC = 0x8122158
    MG_VIRTUAL = &PL_vtbl_glob
    MG_TYPE = '*'
    MG_OBJ = 0x811e5a8
  NAME = "GLOB"
  NAMELEN = 4
  GvSTASH = 0x810f08c   "main"
  GP = 0x8191b20
    SV = 0x810f164
    REFCNT = 1
    IO = 0x810f23c
    FORM = 0x0  
    AV = 0x0
    HV = 0x0
    CV = 0x0
    CVGEN = 0x0
    GPFLAGS = 0x0
    LINE = 6
    FILE = "(null)"
    FLAGS = 0x2
    EGV = 0x0

(perl 5.6+, Event-0.78)

PS: I don't think it is useful to distribute a massive 120k pdf with the
otherwise small distribution, but that's just my unimportant opinion.


-- 
      -----==-                                             |
      ----==-- _                                           |
      ---==---(_)__  __ ____  __       Marc Lehmann      +--
      --==---/ / _ \/ // /\ \/ /       [email protected] |e|
      -=====/_/_//_/\_,_/ /_/\_\       XX11-RIPE         --+
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