The 'standard process' that I know of is this:
> * On other side some people on #d-d says that the standard way is to add
> .1 to the number.
>
Thus, a package with a version number '1.5' will be versioned
'1.5.1'
Then, an exception follows that if the previous upload was a NMU,
in which case the last number is increased. (i.e. after 1.5.1,
1.5.2 is used).
In that respect, developers-reference's statement of
'Adding 0.1' is not quite precisely documenting the current practice.
Binary-only NMUs add a '0.1', which result in 1.5.0.1.
Binary-only NMU after a NMU will result in 1.5.1.1.
regards,
junichi
