> The while statement will always increment s such that
 > it points to the character after the nul, which means
 > it's pointing to space that's either unallocated (the
 > one byte after allocated memory is allowed to be
 > pointed at, but not dereferenced, unlike the byte
 > before allocated memory), or at least garbage.

    Dispute!

    What you say is true with pre-increment, but with post-increment it
evaluates *s and finds it false before it increments s past the nul byte.
Since the falsity terminates the loop, the incremented pointer is not
dereferenced by the loop. That would not occur until the next iteration. It
is permissible to point past the end, but not to dereference it once there.

    As you say, habit. Both methods have their merits. This is the merit of
post-increment.

Best Wishes,
Bill.

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