printf "'%s'\n", join"'", unpack '(A2)*', 'fredx';;
'fr'ed'x'

printf "'%s'\n", join"'", unpack '(a2)*', 'fredx';;
'fr'ed'x'

printf "'%s'\n", join"'", unpack '(Z2)*', 'fredx';;
'fr'ed'x'