what do you mean with The used flags have little different background?

Also note that Here I didn't get undef values, but empty results is not so true: if you put null values as hashref's keys and then you look for the number of keys, ie zero.

If your last sentence is a question, yes i'm using strwaberryperl.

As you understand the redirection, testing on 2008 OS you'll see that Perl 64bit always see it's own part of the registry (18 keys in this example) while 32Bit Perl see the 32bit part with KEY_READ() and the 64bit using the special flag 0x20019|0x0100. Thus confirm that official docs are wrong. See below:

###64bit Perl

Perl MSWin32-x64-multi-thread
access: 0x20019|0x0100

Number of subkeys found: 18



Perl MSWin32-x64-multi-thread
access: KEY_READ()

Number of subkeys found: 18


###32bit Perl

Perl MSWin32-x86-multi-thread
access: 0x20019|0x0100

Number of subkeys found: 18


Perl MSWin32-x86-multi-thread
access: KEY_READ()

Number of subkeys found: 21
[download]

HtH
L*
UPDATE: i was wrong (thanks Corion!) the docs are right:

KEY_WOW64_32KEY (0x0200)
Indicates that an application on 64-bit Windows should operate on the 
+32-bit registry view. 

KEY_WOW64_64KEY (0x0100)
Indicates that an application on 64-bit Windows should operate on the 
+64-bit registry view.
[download]

So the beahvior observed is rigtly documented.

L*

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