Let's say that hypothetically I'm downloading JPGs from a website.

My script is downloading a series of JPGs: 

www.website.com/1/1.jpg
www.website.com/1/2.jpg
www.website.com/1/3.jpg
[...]
www.website.com/2/1.jpg
www.website.com/2/2.jpg
www.website.com/2/3.jpg

[download]
and so on.

And let's say that some of those JPGs, despite their existence being implied, might not exist.

When my code gets to a "bad patch", say there's no 42 folder, it goes on downloading 

www.website.com/42/1.jpg
www.website.com/42/2.jpg
www.website.com/42/3.jpg

[download]
and saving them to disk as .JPG files, but in reality it's grabbing the 404 message from the website.

My question is, what's the easiest way to check for the case when the URL "www.website.com/42/1.jpg" is sending back an HTML "sorry" page, not a JPG?

I'm just using LWP::Simple at the moment with getstore().

Should I do a HEAD request first? Or just get the URL anyway, check its MIME type, and only store if it's IMG/JPG? Or can I trust that a site will always have a 404 response code for a URL that doesn't exist and go by that? What's most efficient? Will I start using LWP::UserAgent instead of Simple?

In reply to download JPG series with error-handling by Anonymous Monk

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