Late complaint but anyway... :-)
It was wrong to call ide_fixstring() on unterminated strings and expecting
them to become terminated strings after that; plus it was useless to add 2
characters padding at the end. When these variables were the fields of 'struct
ide_tape_obj', those bytes were 0 because of the variable of this type being a
static array. When they became local variables, they got garbage bytes at the
end which ide_fixdriveid() either honestly copied when compressing spaces or
just left where they were...
Should've rather changed the string format to print only N characters max...