[1] [DFN[[CODE(URI)@en[gopher:]] [[URI scheme]]]] は、 [[Gopher]]
[[プロトコル]]によりアクセス可能な[[資源]]を識別することができます。

* 仕様書

- [2] [CITE@en[RFC 4266 - The gopher URI Scheme]] ([TIME[2011-05-30 02:19:47 +09:00]] 版) <http://tools.ietf.org/html/rfc4266>

[3] [[IANA]] 登録済み

* 相対 URL

[6] [CODE(URI)@en[[[gopher:]]]] [[URL]] では [[path]] 中で [CODE(URI)@en[[[/]]]]
が通常の[[文字]]としての意味で用いられ、[[ディレクトリー]]階層を表すものとしては使われていません。
従って[[相対URL]]はあまり有用ではありませんが、もし使われたとすれば通常の他の [[URL]]
と同じ規則に従って処理されるとされています [SRC[[[RFC 1630]]]]。
特に、先頭に型情報が付くため、一般にあまり有用な[[相対URL]]を作ることができません [SRC[[[RFC 1808]]]]。

* 起源

[10] 
かつては 
[CODE[gopher:]]
[[URLの起源]]は
[CODE[https:]]
同様の[[項組起源]]とされていました。
現在は一般の
[[URL]]
と同じ[[不透明起源]]に変更されています。

* [CODE[gopher:]] リンクの実利用例

[15] [CITE[CESNET Network Information Centre]], [TIME[2025-10-26T06:27:42.000Z]], [TIME[1998-06-14T00:16:11.710Z]] <https://web.archive.org/web/19980614001552/http://www.mamedia.cz/nic/>

[14] 
[CITE[Hebrew around the Internet.]], [TIME[2025-06-15T14:45:45.000Z]], [TIME[1997-02-10T20:14:00.230Z]] <https://web.archive.org/web/19970210201256/http://shekel.jct.ac.il/~rajwan/hebrew/HEBREW-HOWTO.04-9.html>

[16] 
[CITE[Index of /pub/security]], [TIME[2025-10-26T07:26:02.000Z]], [TIME[1999-02-20T14:37:14.006Z]] <https://web.archive.org/web/19990220143331/http://ftp.uci.agh.edu.pl/pub/security/>


[17] [CITE@en[Old Vintage Computing Research: prior-art-dept.: The hierarchical hypermedia world of Hyper-G]], [TIME[2025-11-01T09:16:52.000Z]], [TIME[2025-11-02T07:35:10.471Z]] <https://oldvcr.blogspot.com/2025/05/prior-art-dept-hierarchical-hypermedia.html>


[18] >>17 リンク先も稼働している稀有なケース! [TIME[2025-11-02T07:35:52.100Z]]

[19] [CITE[Untitled]], [TIME[2025-11-09T14:18:43.000Z]], [TIME[1999-05-01T09:52:37.477Z]] <https://web.archive.org/web/19990501095022/http://www.twinbridge.com/html/clink.html>


* 歴史

= [DEL[[[RFC 1630]] ([[IETF]] [[情報提供]])]] <urn:ietf:rfc:1630>
= [DEL[[[RFC 1738]] ([[IETF]] [[提案標準]])]] <urn:ietf:rfc:1738>

[5] [CITE@en[RFC 1808 - Relative Uniform Resource Locators]] ([TIME[2011-06-04 15:15:57 +09:00]] 版) <http://tools.ietf.org/html/rfc1808#section-2.3>


[4] [CITE[IRC logs: freenode / #whatwg / 20091028]]
([TIME[2009-12-14 01:20:29 +09:00]] 版)
<http://krijnhoetmer.nl/irc-logs/whatwg/20091028#l-608>

>
- [13:25] <hsivonen> wow. gopher: still works in Firefox
- [13:25] <hsivonen> but not in Safari
- [13:26] <gsnedders|work> Safari never supported it, ever
- [13:26] <gsnedders|work> IE7 removed support for Gopher, IIRC
- [13:26] <hsivonen> can't test Opera. Opera keeps bouncing in the Dock and the bouncing frequency isn't stable


[FIG(quote)[
[FIGCAPTION[
[7] [CITE[FSP Proxy]]
([[Radim Kolar, hsn@sanatana.localdomain]] 著, [TIME[2014-09-09 19:52:57 +09:00]] 版)
<http://fsp.sourceforge.net/fsproxy.html>
]FIGCAPTION]

> Because current browsers do not understands fsp:// URLs, FSP proxy understands also gopher:// as alias for fsp://. You need to setup your browser's gopher proxy to this proxy server.
> Doing this cut offs access to gopher servers for you, but they are very rare today. Currently this is only one known way how to get fsp working in your browser.

]FIG]


[8] [CITE@en[libwww-perl/gopher.pm at master · libwww-perl/libwww-perl]]
([TIME[2015-03-16 18:26:55 +09:00]] 版)
<https://github.com/libwww-perl/libwww-perl/blob/master/lib/LWP/Protocol/gopher.pm#L89>

[9] [CITE@en[Remove gopher case from origin algorithm]]
([[rmisev]]著, [TIME[2019-10-21 22:02:15 +09:00]])
<https://github.com/whatwg/url/commit/7ae1c691c96f0d82fafa24c33aa1e8df9ffbf2bc>

[11] [CITE@en[Remove gopher from list of special schemes by achristensen07 · Pull Request #453 · whatwg/url]]
([TIME[2020-05-14 12:44:53 +09:00]])
<https://github.com/whatwg/url/pull/453>

[12] [CITE@en[gopher test updates do not match spec updates · Issue #455 · whatwg/url]]
([TIME[2020-05-14 12:45:11 +09:00]])
<https://github.com/whatwg/url/issues/455>

[13] [CITE@en[Remove gopher's case from origin's algorithm by rmisev · Pull Request #454 · whatwg/url]]
([TIME[2020-05-14 12:45:32 +09:00]])
<https://github.com/whatwg/url/pull/454>