That's not quite accurate. 
$ perl 832144.pl
GLOB(0x84250b8) unix
GLOB(0x84250b8) perlio

GLOB(0x8248600) unix
GLOB(0x8248600) perlio
GLOB(0x8248600) encoding(utf-8-strict)
GLOB(0x8248600) utf8

GLOB(0x82610d8) unix
GLOB(0x82610d8) perlio


$ perl -e'use open qw( :std IO :encoding(UTF-8) ); do $ARGV[0];' 83214
+4.pl
GLOB(0x84dbdc8) unix
GLOB(0x84dbdc8) perlio
GLOB(0x84dbdc8) encoding(utf-8-strict)
GLOB(0x84dbdc8) utf8

GLOB(0x82ff610) unix
GLOB(0x82ff610) perlio
GLOB(0x82ff610) encoding(utf-8-strict)
GLOB(0x82ff610) utf8

GLOB(0x8570378) unix
GLOB(0x8570378) perlio

[download]

The DATA handle is actually the one the parser uses to read the source. use open won't affect the DATA of the file in which the use open occurs since it was opened before the use open was encountered.

use utf8;, on the other hand, will affect the local DATA. You could get some "interesting" interactions.

Your best bet is 

binmode(DATA, ':encoding(UTF-8)');

[download]

In reply to Re^4: Using "binmode ???, ':encoding(UTF-8)" on the result from "qx//" ? by ikegami
in thread Using "binmode ???, ':encoding(UTF-8)" on the result from "qx//" ? by LanX

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