1) Having found a bug report that i would like to work on
- Which is the source file i download? the orig or the dsc? the
debian one or the upstream one?
Just do this:
apt-get source package-name
- Do i need to contact first the maintainer of the package that i
intend to work on some bug? (i guess i would know this if i have read
the debian policy more rigorously, i will do so)
Not necessary - I have patched many packages that I use internally.
However, if you contact the maintainer, or use the maintainer's mailing
list, you can avoid working on the problem at the same time as somebody
else.
2) Having obtained the source, before i start making my modifications
should i apply the existing patches appearing in diff.gz or should i
work directly on the original code?
The apt-get source command will do that for you.
3) Having done my changes do i need to prepare and submit a package
containing the new modified version? Even though i might not need to
offer a package do i need to make sure that the resulting code can be
properly packaged? Or do i simply submit the patch and the maintainers
worry about the rest? What is it more useful for the maintainer?
Just sending a diff to the upstream may be sufficient - it depends on the
type of patch.
If it is Debian specific, you could log the diff in the bug tracking
system too.