Update \since to BeOS R4. This method definitely predates Haiku,
it has existed since at least R4.5 despite not being documented.
Document B_NAME_TOO_LONG return value.
Change-Id: I0816e4e89ae2710f6123e10ee41145a83fdca66f
Reviewed-on: https://review.haiku-os.org/c/haiku/+/6363
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: Adrien Destugues <pulkomandy@pulkomandy.tk>
f18d2effbf