TinyURL does use redirects. Below is an example of the process used.
From a practical sense, it probably makes little difference which method is used. I don't see why one would need TinyURL since we provide the web page URL link markup code right within the text composer box.
If the TinyURL web site is down or out of business, it is my understanding that the links would no longer work.
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TinyURL redirect (from O'ReillyNet)
so the first thing i did was submit the following URL,
http://www.oreillynet.com/pub/au/1303, and they returned
http://tinyurl.com/sr66. not a huge reduction in size, but enough for you to see what they do. and when i chase the URL they returned, i wind up at the page i submited...
so the next thing i did was use wget to see what was actually going back and forth on the wire ... here's what i found
$ wget
http://tinyurl.com/sr66
--14:29:19--
http://tinyurl.com/sr66
=> `sr66'
Resolving tinyurl.com... done.
Connecting to tinyurl.com[216.234.186.14]:80... connected.
HTTP request sent, awaiting response... 302 Found
Location:
http://www.oreillynet.com/pub/au/1303 [following]
--14:29:19--
http://www.oreillynet.com/pub/au/1303
=> `1303'
Resolving
www.oreillynet.com... done.
Connecting to
www.oreillynet.com[208.201.239.37]:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: unspecified [text/html]
[ <=> ] 19,325 36.79K/s
14:29:20 (36.79 KB/s) - `1303' saved [19325]
so looking closely at what happened, wget chased
http://tinyurl.com/sr66, only to have the server return a 302 and another URL,
http://www.oreillynet.com/pub/au/1303. a 302 response code means, in essence, that the server understands what you're asking for, but wants you to know it's temporarily someplace else, and that place is at this URL i'm handing you. so the user-agent (read: browser, or more properly, http-client) should now rerequest the document from this new location. which of course is what wget does, returning the final target document.
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