Interestingly (and somewhat confusingly), the number of the padding characters appears to indicate both how many (6-bit) characters are missing from the last qu

Interestingly (and somewhat confusingly), the number of the padding characters appears to indicate both how many (6-bit) characters are missing from the last quadruple in the output of the encoder and, at the same time, how many (8-bit) bytes will be trimmed from the last triple by the decoder.