[CLUE-Tech] PHP Sessions and Cookies: Brain Cramp

[Matt Gushee]

On Sat, Oct 12, 2002 at 10:38:03PM -0600, Jed S. Baer wrote:

> > $ telnet www.yourserver.com 80
> > GET /jed/login.php
> 
> Well, DOH! I forget about useful stuff like:
> 
> $ HEAD http://localhost/~jbaer/php/itsams/user/login.php

Oh, it's a *local* command. Ah-ha.

$ HEAD http://www.havenrock.com/
200 OK
Connection: close
Date: Sun, 13 Oct 2002 05:06:18 GMT
Accept-Ranges: bytes
ETag: "2417b1-14ac-3d98a786"

Well, I didn't know I had that. So I thought I'd find out a little more.

bash-2.05a$ which HEAD
/usr/bin/HEAD
bash-2.05a$ dpkg -S /usr/bin/HEAD    # Which package provides this file?
libwww-perl: /usr/bin/HEAD           # libwww-perl

And I learned a new HTTP header, too--ETag. From RFC 2616, Section
13.3.2:

  The ETag response-header field value, an entity tag, provides for an
  "opaque" cache validator. ...

This has been very educational.

-- 
Matt Gushee                 When a nation follows the Way,
Englewood, Colorado, USA    Horses bear manure through
mgushee at havenrock.com           its fields;
http://www.havenrock.com/   When a nation ignores the Way,
                            Horses bear soldiers through
                                its streets.
                                
                            --Lao Tzu (Peter Merel, trans.)