oct converts *from* oct/hex/bin (oct in your case).
Conversion from dec is done automatically when needed.
printf converts *to* dec/oct/hex/bin.

>perl -le "printf '%d', '255'
255
>perl -le "printf '0%o', oct '0377'
0377
>perl -le "printf '0x%X', oct '0xFF'
0xFF
>perl -le "printf '0b%b', oct '0b11111111'
0b11111111
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