Re^2: [OT] HTTP downloads and caching

I haven't tried wget --no-cache yet as that cleared the cache last time.

Thankfully wget --no-cache still does the trick.
And I've come across an improvement in the form of wget --spider --no-cache which clears the cache without having to actually download the file.
(This is particularly useful if the cached file is large ... as can be the case with some of the tar.gz files that PPM needs to download.)
I still haven't been ale to work out just where the offending cache is located - though I have established that it's upstream of my router.

It still remains to work out how I can patch Strawberry's ppm utility such that running this wget command in advance is not needed.

Cheers,
Rob

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Re^3: [OT] HTTP downloads and caching by Anonymous Monk on Jun 10, 2017 at 06:19 UTC
My off the cuff guess is that your ISP is running a so called transparent proxy. (Cox?) Also, it sounds like this server is under your control. If so, you should be able to configure your web server to use HTTP to prevent the caching. I've linked to the w3 doc for 1.1, look for the section 14.9 Cache-Control which includes a comment on Pragma: no-cache for HTTP 1.0 There are ways to probe the caches and figure out what is going on but I believe that cache-control should do the trick. The next step is less easy. https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html	[reply]
Re^4: [OT] HTTP downloads and caching by syphilis (Archbishop) on Jun 11, 2017 at 02:26 UTC
Also, it sounds like this server is under your control I don't think it is - though I could be wrong. If it is under my control then I'd have to do a bit of research and learning before I could exercise that control. Back in March I opened a ticket with the company that hosts my website and asked them to mark "all files in (and below) the sisyphusion.tk/ppm directory" as "no-cache". They replied "Your request has been accomplished". Of course they don't provide any info regarding exactly what they've done (they never do), but whatever it was didn't make any difference. Reading various comments/docs about this "no-cache" option I see a lot of "should-do-this" statements and not many "will-do-this" ones. I think the best solution would be to hack PPM to send a "no-cache" argument. Make that the default behaviour, with an option to allow caching via a command line argument. PPM itself uses perl's LWP modules: `C:\>perl -MPPM -le "for(keys(%INC)){print if $_ =~ /LWP/}" LWP/UserAgent.pm LWP/MemberMixin.pm LWP/Simple.pm LWP.pm LWP/Protocol.pm` [download] So, assuming LWP already allows for the passing of the "--no-cache" directive, such a hack might not be too difficult. In the meantime, running `wget --spider --no-cache http://....` is tolerable, if not exactly satisfactory. Thank you for your reply and link ! Cheers, Rob	[reply] [d/l] [select]
Re^4: [OT] HTTP downloads and caching by Anonymous Monk on Jun 10, 2017 at 06:22 UTC
blah, reply to reply is bad but you can probably get away with just setting the cache options on your download directory.	[reply]