* UA-CPU: 欄 (HTTP 要求頭欄)

[2] [[HTTP]] の [DFN[[CODE(HTTP)[UA-CPU:]] [[要求頭欄]]]]は、
[[利用者エージェント]]が動作している [[CPU]]
を指定する欄です。 [CODE(HTTP)[[[UA-[VAR[*]]]]:]] 系頭欄群の一種です。

[4] 仕様書:
この頭欄は [[IETF]] などの標準規格で定義されたものではありません。
実装仕様書もまだ見つかっていません。

[[#comment]]

** 欄本体

[5] 欄本体には、 CPU の名前を指定します。
[[非構造化欄]]と思われます。

次の値が観測されています。
,値,意味,メモ
,[CODE(HTTP)[AMD64]]
,[CODE(HTTP)[ARM OMAP 730]]
,[CODE(HTTP)[Intel(R) PXA255]],
,[CODE(HTTP)[PPC]],Power PC
,[CODE(HTTP)[V830]],
,[CODE(HTTP)[x86]],Intel [VAR[x]]86 系列

[[#comment]]

** 実装

[3] [[WinIE 3]]・[[MacIE]] 3 が他の [CODE(HTTP)[UA-[VAR[*]]:]] 
各欄とともに送り付けていました (これが起源?)。

他の実装例: [[AVE-Front]], [[Device Mosaic]], [[PIE]] 2.0。

[[#comment]]

** メモ

[1] ''Nonstandard HTTP Headers'' <http://web.archive.org/web/20020610043404/http://www.dais.is.tohoku.ac.jp/~kabe/WWW/nonstdhdr.html#UA-CPU>

[6] [CITE@en[Dell Axim "Bad Request" problem reason identified! '''['''Archive''']''' - PPczone.net forums]] ([TIME[2009-01-05 22:12:37 +09:00]] 版) <http://www.ppczone.net/forum/archive/index.php/t-268.html>

>
[PRE(HTTP example code)[
UA-CPU: Intel® PXA250
]PRE]
>
The reason for the problem is the ® character. If that character is present
certain web servers will return with the bad request error. I have narrowed
it down to this character by writing a custom app that sends a GET packet to
http://wireless.cnn.com with custom headers. If the ® is present a "Bad
request" is received, if the ® is ommited the server returns the correct
page.
>
So far the servers that have a problem with the ® symbol have identified
themselves as: Server: Netscape-Enterprise/4.1. I have only checked a
couple sites so I don't know whether the problem is with all instances of
this specific server, nor whether it is limited to servers of that type.
>
FWIW the packet sniffer I use (EtherReal) ALSO doesn't like GET packets with
a field that contains the ®, so perhaps IE is violating the standard for
http GET requests? I don't know.

[[#comment]]

* メモ