While helping feanor_269 dup DATA to STDIN in the chatterbox I came up with the following code (works for me on Sun perl versions 5.004, 5.6, 5.8). The first two statements would seem to be a no-op, and yet it does not work without them. 
$a = tell(DATA);
seek(DATA,$a,0);

open(STDIN, "<&DATA");
while(<STDIN>){
  print "STDIN: $_";
}
__DATA__
Foo
Bar
Quux

[download]
Luckily my initial code was this, else I might not have hit upon that. 
while(<DATA>){
  print "DATA: $_";
}
seek(DATA,0,0);
open(STDIN, "<&DATA");
while(<STDIN>){
  print "STDIN: $_";
}
__DATA__
Foo
Bar
Quux

[download]
Does anybody have an explanation for what's going on with that first snippet?

--
I'm not belgian but I play one on TV.

In reply to Dup oddity OR Is it cargo cult if you wrote it yourself? by belg4mit

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