that's what i mean. it is a pointer of a pointer. The function alloactes the needed memory itself. here is the prove 
sub query_users {
    my ( $self, $filename ) = @_;

    my $func = import_api( 'advapi32', 'QueryUsersOnEncryptedFile', 'P
+P', 'N' );        
    die "Could not import API QueryUsersOnEncryptedFile: $!"
      unless defined $func;
      
    $filename = make_unicode( File::Spec->canonpath($filename) );     
+          
    my $ptr = " " x 4; # 4 == sizeof(void*)
    my $result = $func->Call( "$filename", $ptr );
    print "result: $result\n";
    return undef if $result;
    
    my $address = unpack( "L*", $ptr );
    printf("0x%08x\n", $address);            
}

[download]
i think i have to switch to XS at this point.

In reply to Re^6: Win32::API::Struct: Pointers of Pointers by esskar
in thread Win32::API::Struct: Pointers of Pointers by esskar

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