[squid-users] understanding how Last-Modified is really used...

Folks,

If you have been following along my other questions, I want to use a
proxy on my kiosk to cache downsized images. The problem is that the
system operator can make changes to images, such as rotating them or
cropping them.

If I understand all this correctly, I can change the Last-Modified
header to reflect the last time the image was changed rather then when
the script was run to downsize the image. Correct?

Assuming I can change the Last-Modified header, is there some type of
"pre-fetch" that the proxy does to JUST get the header info as to
knows whether or not to get the generated content?

Assuming there is some type of pre-fetch. Is my impression correct
that I have to handle the pre-fetch correctly within my script (PHP,
by the way) and not do the actual content when receiving a pre-fetch
request? If my impression is correct about this whole thing, how do I
detect that the request is a pre-fetch and not a full fetch,
generically speaking, for I don't know if I am going to be sticking
with PHP;)

Sam
Received on Fri Mar 16 2007 - 10:22:51 MDT