I hope to ear working solutions but i humbly suspect we'll not. I also suspect that this file handle is bring to existence only when logical end of the file is different from the physical one (as you have read in Special Literals) and this is due to the special token __DATA__

If no token is found (i suspect) that anyone that was reading the code close the file before any possible existence of a Perl filehandle. Infact DATA is not available during a BEGIN block, obviously. Also the fact that $. starts just after the token, with the value of 1 make me suspicious. I've still waiting for that trick solution.. but some test is still interesting (oneliners acts like plain file here):

perl -we "print tell DATA"
  Name "main::DATA" used only once: possible typo at -e line 1.
  tell() on unopened filehandle DATA at -e line 1.
  -1

perl -we "print tell DATA;__DATA__" -e"aaa" -e "bbb"                  
+  # uh?! no error!
  0

perl -we "print tell DATA;__DATA__" -e"aaa" -e "bbb" -MO=Deparse
  BEGIN { $^W = 1; }
  print tell DATA;
  __DATA__
  -e syntax OK
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About the fool idea of opening $0 and just for curiosity, was my 7th post here.

L*