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

From: Paul Gilmartin via curl-users <curl-users_at_lists.haxx.se>
Date: Mon, 28 Apr 2025 07:32:07 -0600

On 4/28/25 02:37, Daniel Stenberg via curl-users wrote:
> On Mon, 28 Apr 2025, Aleksei via curl-users wrote:
>
>> I'm trying to implement a "download only if updated on a remote
>> resource" functionality with a curl script using etags.
>>
>> Currently the etag file saved with --etag-save becomes useless after
>> a single update on a remote resource.
>
> I don't understand. Can you elaborate? If the remote resource is
> indeed updated, surely it should download again and update the etag file?
     ...
This sounds like a site I use which, improperly, returns no  ETag in the
headers when Status is 304.  In that case, --etag-save overwrites the
ETag file which "becomes useless."  I've circumvented with a wrapper
script.  I shall not submit an enhancement request for cURL to
accommodate any misbehaving site.

-- 
gil
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Received on 2025-04-28