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go / go / b615ad8fd57f9394db14e403d12061c369379c52
commitb615ad8fd57f9394db14e403d12061c369379c52[log] [tgz]
authorBrad Fitzpatrick <bradfitz@golang.org>Thu Jun 25 12:52:54 2015 +0200
committerBrad Fitzpatrick <bradfitz@golang.org>Thu Jul 09 22:19:41 2015 +0000
tree62bceef37507785526b4f5ff64811c56db06826c
parent4c332508f92cc39eaa4c10ed005a615776280a04 [diff]
net: add mechanisms to force go or cgo lookup, and to debug default strategy

GODEBUG=netdns=1 prints a one-time strategy decision. (cgo or go DNS lookups)
GODEBUG=netdns=2 prints the per-lookup strategy as a function of the hostname.

The new "netcgo" build tag forces cgo DNS lookups.

GODEBUG=netdns=go (or existing build tag "netgo") forces Go DNS resolution.
GODEBUG=netdns=cgo (or new build tag "netcgo") forces libc DNS resolution.

Options can be combined with e.g. GODEBUG=netdns=go+1 or GODEBUG=netdns=2+cgo.

Fixes #11322
Fixes #11450

Change-Id: I7a67e9f759fd0a02320e7803f9ded1638b19e861
Reviewed-on: https://go-review.googlesource.com/11584
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
7 files changed
tree: 62bceef37507785526b4f5ff64811c56db06826c
  1. api/
  2. doc/
  3. lib/
  4. misc/
  5. src/
  6. test/
  7. .gitattributes
  8. .gitignore
  9. AUTHORS
  10. CONTRIBUTING.md
  11. CONTRIBUTORS
  12. favicon.ico
  13. LICENSE
  14. PATENTS
  15. README.md
  16. robots.txt
README.md

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For example, if you extracted the tar file into $HOME/go, you might put the following in your .profile:

export GOROOT=$HOME/go
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See https://golang.org/doc/install or doc/install.html for more details.