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Re: [RFE] Improve etag handling with --etag-compare-update

From: Daniel Stenberg via curl-users <curl-users_at_lists.haxx.se>
Date: Tue, 29 Apr 2025 08:05:24 +0200 (CEST)

On Tue, 29 Apr 2025, Aleksei wrote:

> I'm asking for "and update the etag file" part to be done by curl.
>
> Scenario:
> 1) curl downloads a webpage, saving etag file in file0.etag

Something like this:

curl --etag-save file0.etag $URL

> 2) website updates a webpage (update 1)
> 3) curl uses "--etag-compare file0.etag" and re-downloads the page -
> so far so good

Download the file if changed, update the etag file:

curl --etag-compare file0.etag --etag-save file0.etag $URL

> 4) website updates a webpage (update 2)
> 5) How do I check that webpage is updated now? "--etag-compare
> file0.etag" will re-download even if update 2 has been downloaded

You repeat the command above:

curl --etag-compare file0.etag --etag-save file0.etag $URL

... which only downloads the URL again if it is different than the last
download.

-- 
  / daniel.haxx.se || https://rock-solid.curl.dev
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Received on 2025-04-29