syscall: document Sendfile semantics
syscall.Sendfile behavior differs significantly between operating
systems.
Document the platform-specific behavior for the offset argument and
partial write reporting on Linux versus BSD-derived systems.
Fixes #64044
Change-Id: I93f740c3e2df911a10bf0884ffab218d4bb4e5fc
GitHub-Last-Rev:
a11b898bb98f2a136caaba875033f1c155c1c872
GitHub-Pull-Request: golang/go#77224
Reviewed-on: https://go-review.googlesource.com/c/go/+/737122
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>