use Fatal "open";

open my $fh, "<:raw", \"foo";
print <$fh>, "\n";

--> dies with:
Can't open(GLOB(0x65ea40), <:raw, SCALAR(0x65eaa0)): No such file or directory at (eval 1) line 3
        main::__ANON__('GLOB(0x65ea40)', '<:raw', 'SCALAR(0x65eaa0)') called at ./openstr.pl line 5