@eramoto, thanks for your PR! By analyzing the history of the files in this pull request, we identified @bagder, @dfandrich and @rousskov to be potential reviewers.

allows us to access non-proxied hosts even if using NO_PROXY env var with --proxy option

It isn't very clear to me exactly how this works (after this patch). Are you saying that the proxy given with --proxy now is used even if the host in the URL is mentioned in the NO_PROXY environment variable?

http_proxy, no_proxy, --noproxy and --proxy all interact here. Do you think you can clarify how in the docs, like in the --proxy or --noproxy section?

@bagder eramoto is saying that NO_PROXY environment variable is ignored when used with --proxy option.

So, for example, before this patch

no_proxy=127.0.0.1,localhost,192.168.1.1 curl --proxy http://proxy.example.com:8080/  http://somewhere.example.com/
# -> Accessed through proxy

no_proxy=127.0.0.1,localhost,192.168.1.1 curl --proxy http://proxy.example.com:8080/  http://192.168.1.1/
# -> Accessed through proxy ** NOT INTENDED **

after this patch

no_proxy=127.0.0.1,localhost,192.168.1.1 curl --proxy http://proxy.example.com:8080/  http://somewhere.example.com/
# -> Accessed through proxy

no_proxy=127.0.0.1,localhost,192.168.1.1 curl --proxy http://proxy.example.com:8080/  http://192.168.1.1/
# -> Accessed directly, as intended.

@eramoto please tell me if this is not what you meant.

That's a crystal clear explanation that I understand perfectly. @eramoto, do you think you could also add something to the docs in this vein that lets future users understand the priorities and what overrides what?

@bagder

I add the following descriptions to the curl man-page:

• --noproxy option does not override NO_PROXY env var.
• If specify both of --noproxy option and NO_PROXY env var, both are effective.
• Since 7.52.0, NO_PROXY env var is effective even if specify --proxy option.

Cloud you confirm this commit.

Thank you for your reviews. @bagder

I fixed these typos.

Do we really need the environment variable for NOPROXY to override the command line option --noproxy? It feels like against how several other options works. We generally let command line options override environment variables so that if you know what you want to can specify that exactly with command line options and if you rather want to let the environment control you don't use the command line option.

Because it is better to change to the behavior that are similar to other options,
I now rewrite lib/url.c and docs/curl.1 to override the environment variable NO_PROXY
due to the command line option --noproxy.

Cloud you wait a few days. @bagder

I changed as following:

• The command line option --noproxy overrides the environment variable NO_PROXY.
• Rewrite this behavior into the individual option documentation page noproxy.d.

Cloud you check this commits. @bagder

I thought we agreed that the command line options should override the environment variables? Yet your man page edit says:

this environment variable disable the proxy even if specify
--proxy option. That is
NO_PROXY=direct.example.com curl -x http://proxy.example.com http://direct.example.com
accesses the target URL directly.

@bagder
I think an option should override the corresponding env var, like --noproxy overrides NO_PROXY,
but not for different env var, like --proxy(-x) option does not override NO_PROXY.

Hm, yes I think you're right. Thanks.

@eramoto , Can you please rebase your patch set (and squash what you think is reasonable), and update the release version number mentioned in the docs where this change is included (7.52.2 is now the next possible release number) and I promise to do my best to merge it when done?

(basically, you can skip changing curl.1 completely, we'll generate that based on the cmdline-opts/* docs anyway)

I rebased and squashed my patch set (, and updated the release version number in the docs).

@bagder
Could you please merge this new patch set?

Thanks a lot for your work and patience on this!