Implement open( my $fh, ...) and similar.

  Set flag in op.c for "constructor ops"
  In pp_rv2gv, if flag is set and arg is PADSV and uninit
  vivify as reference to a detached GV.
  (Name of GV is the pad name.)
This scheme should "just work" for pipe/socket etc. too.

#if 0 out the open(FH,undef) for now.
Change t/io/open.t to test open(my $fh,...)

p4raw-id: //depot/perl@3326

1 files changed, 11 insertions, 2 deletions

diff --git a/op.c b/op.c
index 2b6107e729..5e2d593225 100644
--- a/op.c
+++ b/op.c
@@ -4780,11 +4780,20 @@ ck_fun(OP *o)
 		    }
 		    else {
 			I32 flags = OPf_SPECIAL;
+			I32 private = 0;
 			/* is this op a FH constructor? */
-			if (is_handle_constructor(o,numargs))
-			    flags = 0;
+			if (is_handle_constructor(o,numargs)) {
+			    /* Set a flag to tell rv2gv to vivify 
+			     * need to "prove" flag does not mean something
+			     * else already - NI-S 1999/05/07
+			     */ 
+			    flags   = 0;                         
+			    private = OPpDEREF;
+			}
 			kid->op_sibling = 0;
 			kid = newUNOP(OP_RV2GV, flags, scalar(kid));
+			if (private)
+			    kid->op_private |= private;
 		    }
 		    kid->op_sibling = sibl;
 		    *tokid = kid;