use constant INVALID_FILE_HANDLE => -1;

my $hFile= CreateFileW(
    $wPath,
    GENERIC_READ()|GENERIC_WRITE(),
    FILE_SHARE_READ()|FILE_SHARE_WRITE(), [],
    OPEN_EXISTING(), 0, [] );

INVALID_FILE_HANDLE != $hFile
    or  die "Can't open: $^E\n";