

A Trick For Caching And Expiring Static Web Resources - mdemare
http://blog.mdemare.info/2008/07/27/a-trick-for-caching-and-expiring-static-web-resources/

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louislouis
Might be easier to do something like:

yourFileName.jpg?lastUpdated=12345

where 12345 would be the unix time of last file change.

