internal/socket: support MSG_DONTWAIT

Explicitly handle MSG_DONTWAIT in read and send calls on platforms where this is defined, to get the per-call non-blocking behavior as would be expected when calling readmsg/sendmsg in C.
When MSG_DONTWAIT is set, we always return true from the function passed to syscall.RawConn.Read/Write, to avoid entering the polling state.

Fixes golang/go#46891

Change-Id: I4809577477554db1c45b6f4825a03d98208199d7
GitHub-Last-Rev: 4022e9b52c4375536e23162a88e5aa4d5637f134
GitHub-Pull-Request: golang/net#108
Reviewed-on: https://go-review.googlesource.com/c/net/+/333469
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Damien Neil <dneil@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
Trust: Damien Neil <dneil@google.com>
5 files changed
tree: 0fc98c127a5ee3acb007b13ed1687cbcf37e19aa
  1. .gitattributes
  2. .gitignore
  3. AUTHORS
  4. CONTRIBUTING.md
  5. CONTRIBUTORS
  6. LICENSE
  7. PATENTS
  8. README.md
  9. bpf/
  10. codereview.cfg
  11. context/
  12. dict/
  13. dns/
  14. go.mod
  15. go.sum
  16. html/
  17. http/
  18. http2/
  19. icmp/
  20. idna/
  21. internal/
  22. ipv4/
  23. ipv6/
  24. lif/
  25. nettest/
  26. netutil/
  27. proxy/
  28. publicsuffix/
  29. route/
  30. trace/
  31. webdav/
  32. websocket/
  33. xsrftoken/
README.md

Go Networking

Go Reference

This repository holds supplementary Go networking libraries.

Download/Install

The easiest way to install is to run go get -u golang.org/x/net. You can also manually git clone the repository to $GOPATH/src/golang.org/x/net.

Report Issues / Send Patches

This repository uses Gerrit for code changes. To learn how to submit changes to this repository, see https://golang.org/doc/contribute.html. The main issue tracker for the net repository is located at https://github.com/golang/go/issues. Prefix your issue with “x/net:” in the subject line, so it is easy to find.