In terms of the type of shift you get, the important thing is the type of the value that you're shifting. A classic source of bugs is when you shift a literal to, say, mask off bits. For example, if you wanted to drop the left-most bit of an unsigned integer, then you might try this as your mask:
~0 >> 1
Unfortunately, this will get you into trouble because the mask will have all of its bits set because the value being shifted (~0) is signed, thus an arithmetic shift is performed. Instead, you'd want to force a logical shift by explicitly declaring the value as unsigned, i.e. by doing something like this:
~0U >> 1;