Minor type nits in string arguments example

[noncombatant]

Re: http://jakegoulding.com/rust-ffi-omnibus/string_arguments/

Rust count returns usize; rather than (potentially down-)casting to uint32_t, does it make sense to change the example to return size_t? And then you don't need a cast.

In the C code, the printf format should be %u, or %zu if you use size_t. (Also you'll want to use %u in /slice_arguments/, and in /tuples. Or use int32_t, for which %d is appropriate.)

[Enet4]

The second part of this has been addressed in #76. About returning a count usize, it sounds reasonable, since it's heavily related to the size of some object in memory. But I wouldn't find either one particularly incorrect either, as long as the output is sure not to overflow a uint32_t. Maybe this is just a decision to be made on a case-by-case basis, depending on whether you wish to abstract away from the (potentially awkward) definition of size_t. There would be cases where this is unambiguous, of course: if the library was providing the number of views on a YouTube video, we'd totally go for a uint64_t instead.

[Stargateur]

In the C code, the printf format should be %u, or %zu if you use size_t.

%u is not correct if used for size_t, you must use the z specifier.

Or use int32_t, for which %d is appropriate.)

No, d is not appropriate for int32_t, one correct could be PRId32