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diff --git a/man7/uri.7 b/man7/uri.7 deleted file mode 100644 index 6823b45..0000000 --- a/man7/uri.7 +++ /dev/null @@ -1,761 +0,0 @@ -.\" (C) Copyright 1999-2000 David A. Wheeler (dwheeler@dwheeler.com) -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" Fragments of this document are directly derived from IETF standards. -.\" For those fragments which are directly derived from such standards, -.\" the following notice applies, which is the standard copyright and -.\" rights announcement of The Internet Society: -.\" -.\" Copyright (C) The Internet Society (1998). All Rights Reserved. -.\" This document and translations of it may be copied and furnished to -.\" others, and derivative works that comment on or otherwise explain it -.\" or assist in its implementation may be prepared, copied, published -.\" and distributed, in whole or in part, without restriction of any -.\" kind, provided that the above copyright notice and this paragraph are -.\" included on all such copies and derivative works. However, this -.\" document itself may not be modified in any way, such as by removing -.\" the copyright notice or references to the Internet Society or other -.\" Internet organizations, except as needed for the purpose of -.\" developing Internet standards in which case the procedures for -.\" copyrights defined in the Internet Standards process must be -.\" followed, or as required to translate it into languages other than English. -.\" -.\" Modified Fri Jul 25 23:00:00 1999 by David A. Wheeler (dwheeler@dwheeler.com) -.\" Modified Fri Aug 21 23:00:00 1999 by David A. Wheeler (dwheeler@dwheeler.com) -.\" Modified Tue Mar 14 2000 by David A. Wheeler (dwheeler@dwheeler.com) -.\" -.TH uri 7 2023-10-31 "Linux man-pages 6.7" -.SH NAME -uri, url, urn \- uniform resource identifier (URI), including a URL or URN -.SH SYNOPSIS -.SY "\fIURI\fP \fR=\fP" -.RI [\~ absoluteURI -| -.IR relativeURI \~] -.RB [\~\[dq] # \[dq]\~\c -.IR fragment \~] -.YS -.P -.SY "\fIabsoluteURI\fP \fR=\fP" -.I scheme\~\c -.RB \[dq] : \[dq] -.RI (\~ hierarchical_part -| -.IR opaque_part \~) -.YS -.P -.SY "\fIrelativeURI\fP \fR=\fP" -.RI (\~ net_path -| -.I absolute_path -| -.IR relative_path \~) -.RB [\~\[dq] ? \[dq]\~\c -.IR query \~] -.YS -.P -.SY "\fIscheme\fP \fR=\fP" -.RB \[dq] http \[dq] -| -.RB \[dq] ftp \[dq] -| -.RB \[dq] gopher \[dq] -| -.RB \[dq] mailto \[dq] -| -.RB \[dq] news \[dq] -| -.RB \[dq] telnet \[dq] -| -.RB \[dq] file \[dq] -| -.RB \[dq] ftp \[dq] -| -.RB \[dq] man \[dq] -| -.RB \[dq] info \[dq] -| -.RB \[dq] whatis \[dq] -| -.RB \[dq] ldap \[dq] -| -.RB \[dq] wais \[dq] -| \&... -.YS -.P -.SY "\fIhierarchical_part\fP \fR=\fP" -.RI (\~ net_path -| -.IR absolute_path \~) -.RB [\~\[dq] ? \[dq]\~\c -.IR query \~] -.YS -.P -.SY "\fInet_path\fP \fR=\fP" -.RB \[dq] // \[dq]\~\c -.I authority -.RI [\~ absolute_path \~] -.YS -.P -.SY "\fIabsolute_path\fP \fR=\fP" -.RB \[dq] / \[dq]\~\c -.I path_segments -.YS -.P -.SY "\fIrelative_path\fP \fR=\fP" -.I relative_segment -.RI [\~ absolute_path \~] -.YS -.SH DESCRIPTION -A Uniform Resource Identifier (URI) is a short string of characters -identifying an abstract or physical resource (for example, a web page). -A Uniform Resource Locator (URL) is a URI -that identifies a resource through its primary access -mechanism (e.g., its network "location"), rather than -by name or some other attribute of that resource. -A Uniform Resource Name (URN) is a URI -that must remain globally unique and persistent even when -the resource ceases to exist or becomes unavailable. -.P -URIs are the standard way to name hypertext link destinations -for tools such as web browsers. -The string "http://www.kernel.org" is a URL (and thus it -is also a URI). -Many people use the term URL loosely as a synonym for URI -(though technically URLs are a subset of URIs). -.P -URIs can be absolute or relative. -An absolute identifier refers to a resource independent of -context, while a relative -identifier refers to a resource by describing the difference -from the current context. -Within a relative path reference, the complete path segments "." and -".." have special meanings: "the current hierarchy level" and "the -level above this hierarchy level", respectively, just like they do in -UNIX-like systems. -A path segment which contains a colon -character can't be used as the first segment of a relative URI path -(e.g., "this:that"), because it would be mistaken for a scheme name; -precede such segments with ./ (e.g., "./this:that"). -Note that descendants of MS-DOS (e.g., Microsoft Windows) replace -devicename colons with the vertical bar ("|") in URIs, so "C:" becomes "C|". -.P -A fragment identifier, -if included, -refers to a particular named portion (fragment) of a resource; -text after a \[aq]#\[aq] identifies the fragment. -A URI beginning with \[aq]#\[aq] -refers to that fragment in the current resource. -.SS Usage -There are many different URI schemes, each with specific -additional rules and meanings, but they are intentionally made to be -as similar as possible. -For example, many URL schemes -permit the authority to be the following format, called here an -.I ip_server -(square brackets show what's optional): -.P -.IR "ip_server = " [ user " [ : " password " ] @ ] " host " [ : " port ] -.P -This format allows you to optionally insert a username, -a user plus password, and/or a port number. -The -.I host -is the name of the host computer, either its name as determined by DNS -or an IP address (numbers separated by periods). -Thus the URI -<http://fred:fredpassword@example.com:8080/> -logs into a web server on host example.com -as fred (using fredpassword) using port 8080. -Avoid including a password in a URI if possible because of the many -security risks of having a password written down. -If the URL supplies a username but no password, and the remote -server requests a password, the program interpreting the URL -should request one from the user. -.P -Here are some of the most common schemes in use on UNIX-like systems -that are understood by many tools. -Note that many tools using URIs also have internal schemes or specialized -schemes; see those tools' documentation for information on those schemes. -.P -.B "http \- Web (HTTP) server" -.P -.RI http:// ip_server / path -.br -.RI http:// ip_server / path ? query -.P -This is a URL accessing a web (HTTP) server. -The default port is 80. -If the path refers to a directory, the web server will choose what -to return; usually if there is a file named "index.html" or "index.htm" -its content is returned, otherwise, a list of the files in the current -directory (with appropriate links) is generated and returned. -An example is <http://lwn.net>. -.P -A query can be given in the archaic "isindex" format, consisting of a -word or phrase and not including an equal sign (=). -A query can also be in the longer "GET" format, which has one or more -query entries of the form -.IR key = value -separated by the ampersand character (&). -Note that -.I key -can be repeated more than once, though it's up to the web server -and its application programs to determine if there's any meaning to that. -There is an unfortunate interaction with HTML/XML/SGML and -the GET query format; when such URIs with more than one key -are embedded in SGML/XML documents (including HTML), the ampersand -(&) has to be rewritten as &. -Note that not all queries use this format; larger forms -may be too long to store as a URI, so they use a different -interaction mechanism (called POST) which does -not include the data in the URI. -See the Common Gateway Interface specification at -.UR http://www.w3.org\:/CGI -.UE -for more information. -.P -.B "ftp \- File Transfer Protocol (FTP)" -.P -.RI ftp:// ip_server / path -.P -This is a URL accessing a file through the file transfer protocol (FTP). -The default port (for control) is 21. -If no username is included, the username "anonymous" is supplied, and -in that case many clients provide as the password the requestor's -Internet email address. -An example is -<ftp://ftp.is.co.za/rfc/rfc1808.txt>. -.P -.B "gopher \- Gopher server" -.P -.RI gopher:// ip_server / "gophertype selector" -.br -.RI gopher:// ip_server / "gophertype selector" %09 search -.br -.RI gopher:// ip_server / "gophertype selector" %09 search %09 gopher+_string -.br -.P -The default gopher port is 70. -.I gophertype -is a single-character field to denote the -Gopher type of the resource to -which the URL refers. -The entire path may also be empty, in -which case the delimiting "/" is also optional and the gophertype -defaults to "1". -.P -.I selector -is the Gopher selector string. -In the Gopher protocol, -Gopher selector strings are a sequence of octets which may contain -any octets except 09 hexadecimal (US-ASCII HT or tab), 0A hexadecimal -(US-ASCII character LF), and 0D (US-ASCII character CR). -.P -.B "mailto \- Email address" -.P -.RI mailto: email-address -.P -This is an email address, usually of the form -.IR name @ hostname . -See -.BR mailaddr (7) -for more information on the correct format of an email address. -Note that any % character must be rewritten as %25. -An example is <mailto:dwheeler@dwheeler.com>. -.P -.B "news \- Newsgroup or News message" -.P -.RI news: newsgroup-name -.br -.RI news: message-id -.P -A -.I newsgroup-name -is a period-delimited hierarchical name, such as -"comp.infosystems.www.misc". -If <newsgroup-name> is "*" (as in <news:*>), it is used to refer -to "all available news groups". -An example is <news:comp.lang.ada>. -.P -A -.I message-id -corresponds to the Message-ID of -.UR http://www.ietf.org\:/rfc\:/rfc1036.txt -IETF RFC\ 1036, -.UE -without the enclosing "<" -and ">"; it takes the form -.IR unique @ full_domain_name . -A message identifier may be distinguished from a news group name by the -presence of the "@" character. -.P -.B "telnet \- Telnet login" -.P -.RI telnet:// ip_server / -.P -The Telnet URL scheme is used to designate interactive text services that -may be accessed by the Telnet protocol. -The final "/" character may be omitted. -The default port is 23. -An example is <telnet://melvyl.ucop.edu/>. -.P -.B "file \- Normal file" -.P -.RI file:// ip_server / path_segments -.br -.RI file: path_segments -.P -This represents a file or directory accessible locally. -As a special case, -.I ip_server -can be the string "localhost" or the empty -string; this is interpreted as "the machine from which the URL is -being interpreted". -If the path is to a directory, the viewer should display the -directory's contents with links to each containee; -not all viewers currently do this. -KDE supports generated files through the URL <file:/cgi-bin>. -If the given file isn't found, browser writers may want to try to expand -the filename via filename globbing -(see -.BR glob (7) -and -.BR glob (3)). -.P -The second format (e.g., <file:/etc/passwd>) -is a correct format for referring to -a local file. -However, older standards did not permit this format, -and some programs don't recognize this as a URI. -A more portable syntax is to use an empty string as the server name, -for example, -<file:///etc/passwd>; this form does the same thing -and is easily recognized by pattern matchers and older programs as a URI. -Note that if you really mean to say "start from the current location", don't -specify the scheme at all; use a relative address like <../test.txt>, -which has the side-effect of being scheme-independent. -An example of this scheme is <file:///etc/passwd>. -.P -.B "man \- Man page documentation" -.P -.RI man: command-name -.br -.RI man: command-name ( section ) -.P -This refers to local online manual (man) reference pages. -The command name can optionally be followed by a -parenthesis and section number; see -.BR man (7) -for more information on the meaning of the section numbers. -This URI scheme is unique to UNIX-like systems (such as Linux) -and is not currently registered by the IETF. -An example is <man:ls(1)>. -.P -.B "info \- Info page documentation" -.P -.RI info: virtual-filename -.br -.RI info: virtual-filename # nodename -.br -.RI info:( virtual-filename ) -.br -.RI info:( virtual-filename ) nodename -.P -This scheme refers to online info reference pages (generated from -texinfo files), -a documentation format used by programs such as the GNU tools. -This URI scheme is unique to UNIX-like systems (such as Linux) -and is not currently registered by the IETF. -As of this writing, GNOME and KDE differ in their URI syntax -and do not accept the other's syntax. -The first two formats are the GNOME format; in nodenames all spaces -are written as underscores. -The second two formats are the KDE format; -spaces in nodenames must be written as spaces, even though this -is forbidden by the URI standards. -It's hoped that in the future most tools will understand all of these -formats and will always accept underscores for spaces in nodenames. -In both GNOME and KDE, if the form without the nodename is used the -nodename is assumed to be "Top". -Examples of the GNOME format are <info:gcc> and <info:gcc#G++_and_GCC>. -Examples of the KDE format are <info:(gcc)> and <info:(gcc)G++ and GCC>. -.P -.B "whatis \- Documentation search" -.P -.RI whatis: string -.P -This scheme searches the database of short (one-line) descriptions of -commands and returns a list of descriptions containing that string. -Only complete word matches are returned. -See -.BR whatis (1). -This URI scheme is unique to UNIX-like systems (such as Linux) -and is not currently registered by the IETF. -.P -.B "ghelp \- GNOME help documentation" -.P -.RI ghelp: name-of-application -.P -This loads GNOME help for the given application. -Note that not much documentation currently exists in this format. -.P -.B "ldap \- Lightweight Directory Access Protocol" -.P -.RI ldap:// hostport -.br -.RI ldap:// hostport / -.br -.RI ldap:// hostport / dn -.br -.RI ldap:// hostport / dn ? attributes -.br -.RI ldap:// hostport / dn ? attributes ? scope -.br -.RI ldap:// hostport / dn ? attributes ? scope ? filter -.br -.RI ldap:// hostport / dn ? attributes ? scope ? filter ? extensions -.P -This scheme supports queries to the -Lightweight Directory Access Protocol (LDAP), a protocol for querying -a set of servers for hierarchically organized information -(such as people and computing resources). -See -.UR http://www.ietf.org\:/rfc\:/rfc2255.txt -RFC\ 2255 -.UE -for more information on the LDAP URL scheme. -The components of this URL are: -.TP -hostport -the LDAP server to query, written as a hostname optionally followed by -a colon and the port number. -The default LDAP port is TCP port 389. -If empty, the client determines which the LDAP server to use. -.TP -dn -the LDAP Distinguished Name, which identifies -the base object of the LDAP search (see -.UR http://www.ietf.org\:/rfc\:/rfc2253.txt -RFC\ 2253 -.UE -section 3). -.TP -attributes -a comma-separated list of attributes to be returned; -see RFC\ 2251 section 4.1.5. -If omitted, all attributes should be returned. -.TP -scope -specifies the scope of the search, which can be one of -"base" (for a base object search), "one" (for a one-level search), -or "sub" (for a subtree search). -If scope is omitted, "base" is assumed. -.TP -filter -specifies the search filter (subset of entries -to return). -If omitted, all entries should be returned. -See -.UR http://www.ietf.org\:/rfc\:/rfc2254.txt -RFC\ 2254 -.UE -section 4. -.TP -extensions -a comma-separated list of type=value -pairs, where the =value portion may be omitted for options not -requiring it. -An extension prefixed with a \[aq]!\[aq] is critical -(must be supported to be valid), otherwise it is noncritical (optional). -.P -LDAP queries are easiest to explain by example. -Here's a query that asks ldap.itd.umich.edu for information about -the University of Michigan in the U.S.: -.P -.nf -ldap://ldap.itd.umich.edu/o=University%20of%20Michigan,c=US -.fi -.P -To just get its postal address attribute, request: -.P -.nf -ldap://ldap.itd.umich.edu/o=University%20of%20Michigan,c=US?postalAddress -.fi -.P -To ask a host.com at port 6666 for information about the person -with common name (cn) "Babs Jensen" at University of Michigan, request: -.P -.nf -ldap://host.com:6666/o=University%20of%20Michigan,c=US??sub?(cn=Babs%20Jensen) -.fi -.P -.B "wais \- Wide Area Information Servers" -.P -.RI wais:// hostport / database -.br -.RI wais:// hostport / database ? search -.br -.RI wais:// hostport / database / wtype / wpath -.P -This scheme designates a WAIS database, search, or document -(see -.UR http://www.ietf.org\:/rfc\:/rfc1625.txt -IETF RFC\ 1625 -.UE -for more information on WAIS). -Hostport is the hostname, optionally followed by a colon and port number -(the default port number is 210). -.P -The first form designates a WAIS database for searching. -The second form designates a particular search of the WAIS database -.IR database . -The third form designates a particular document within a WAIS -database to be retrieved. -.I wtype -is the WAIS designation of the type of the object and -.I wpath -is the WAIS document-id. -.P -.B "other schemes" -.P -There are many other URI schemes. -Most tools that accept URIs support a set of internal URIs -(e.g., Mozilla has the about: scheme for internal information, -and the GNOME help browser has the toc: scheme for various starting -locations). -There are many schemes that have been defined but are not as widely -used at the current time -(e.g., prospero). -The nntp: scheme is deprecated in favor of the news: scheme. -URNs are to be supported by the urn: scheme, with a hierarchical name space -(e.g., urn:ietf:... would identify IETF documents); at this time -URNs are not widely implemented. -Not all tools support all schemes. -.SS Character encoding -URIs use a limited number of characters so that they can be -typed in and used in a variety of situations. -.P -The following characters are reserved, that is, they may appear in a -URI but their use is limited to their reserved purpose -(conflicting data must be escaped before forming the URI): -.IP -.in +4n -.EX -; / ? : @ & = + $ , -.EE -.in -.P -Unreserved characters may be included in a URI. -Unreserved characters -include uppercase and lowercase Latin letters, -decimal digits, and the following -limited set of punctuation marks and symbols: -.IP -.in +4n -.EX -\- _ . ! \[ti] * ' ( ) -.EE -.in -.P -All other characters must be escaped. -An escaped octet is encoded as a character triplet, consisting of the -percent character "%" followed by the two hexadecimal digits -representing the octet code (you can use uppercase or lowercase letters -for the hexadecimal digits). -For example, a blank space must be escaped -as "%20", a tab character as "%09", and the "&" as "%26". -Because the percent "%" character always has the reserved purpose of -being the escape indicator, it must be escaped as "%25". -It is common practice to escape space characters as the plus symbol (+) -in query text; this practice isn't uniformly defined -in the relevant RFCs (which recommend %20 instead) but any tool accepting -URIs with query text should be prepared for them. -A URI is always shown in its "escaped" form. -.P -Unreserved characters can be escaped without changing the semantics -of the URI, but this should not be done unless the URI is being used -in a context that does not allow the unescaped character to appear. -For example, "%7e" is sometimes used instead of "\[ti]" in an HTTP URL -path, but the two are equivalent for an HTTP URL. -.P -For URIs which must handle characters outside the US ASCII character set, -the HTML 4.01 specification (section B.2) and -IETF RFC\~3986 (last paragraph of section 2.5) -recommend the following approach: -.IP (1) 5 -translate the character sequences into UTF-8 (IETF RFC\~3629)\[em]see -.BR utf\-8 (7)\[em]and -then -.IP (2) -use the URI escaping mechanism, that is, -use the %HH encoding for unsafe octets. -.SS Writing a URI -When written, URIs should be placed inside double quotes -(e.g., "http://www.kernel.org"), -enclosed in angle brackets (e.g., <http://lwn.net>), -or placed on a line by themselves. -A warning for those who use double-quotes: -.B never -move extraneous punctuation (such as the period ending a sentence or the -comma in a list) -inside a URI, since this will change the value of the URI. -Instead, use angle brackets instead, or -switch to a quoting system that never includes extraneous characters -inside quotation marks. -This latter system, called the 'new' or 'logical' quoting system by -"Hart's Rules" and the "Oxford Dictionary for Writers and Editors", -is preferred practice in Great Britain and in various European languages. -Older documents suggested inserting the prefix "URL:" -just before the URI, but this form has never caught on. -.P -The URI syntax was designed to be unambiguous. -However, as URIs have become commonplace, traditional media -(television, radio, newspapers, billboards, etc.) have increasingly -used abbreviated URI references consisting of -only the authority and path portions of the identified resource -(e.g., <www.w3.org/Addressing>). -Such references are primarily -intended for human interpretation rather than machine, with the -assumption that context-based heuristics are sufficient to complete -the URI (e.g., hostnames beginning with "www" are likely to have -a URI prefix of "http://" and hostnames beginning with "ftp" likely -to have a prefix of "ftp://"). -Many client implementations heuristically resolve these references. -Such heuristics may -change over time, particularly when new schemes are introduced. -Since an abbreviated URI has the same syntax as a relative URL path, -abbreviated URI references cannot be used where relative URIs are -permitted, and can be used only when there is no defined base -(such as in dialog boxes). -Don't use abbreviated URIs as hypertext links inside a document; -use the standard format as described here. -.SH STANDARDS -.UR http://www.ietf.org\:/rfc\:/rfc2396.txt -(IETF RFC\ 2396) -.UE , -.UR http://www.w3.org\:/TR\:/REC\-html40 -(HTML 4.0) -.UE . -.SH NOTES -Any tool accepting URIs (e.g., a web browser) on a Linux system should -be able to handle (directly or indirectly) all of the -schemes described here, including the man: and info: schemes. -Handling them by invoking some other program is -fine and in fact encouraged. -.P -Technically the fragment isn't part of the URI. -.P -For information on how to embed URIs (including URLs) in a data format, -see documentation on that format. -HTML uses the format <A HREF="\fIuri\fP"> -.I text -</A>. -Texinfo files use the format @uref{\fIuri\fP}. -Man and mdoc have the recently added UR macro, or just include the -URI in the text (viewers should be able to detect :// as part of a URI). -.P -The GNOME and KDE desktop environments currently vary in the URIs -they accept, in particular in their respective help browsers. -To list man pages, GNOME uses <toc:man> while KDE uses <man:(index)>, and -to list info pages, GNOME uses <toc:info> while KDE uses <info:(dir)> -(the author of this man page prefers the KDE approach here, though a more -regular format would be even better). -In general, KDE uses <file:/cgi-bin/> as a prefix to a set of generated -files. -KDE prefers documentation in HTML, accessed via the -<file:/cgi-bin/helpindex>. -GNOME prefers the ghelp scheme to store and find documentation. -Neither browser handles file: references to directories at the time -of this writing, making it difficult to refer to an entire directory with -a browsable URI. -As noted above, these environments differ in how they handle the -info: scheme, probably the most important variation. -It is expected that GNOME and KDE -will converge to common URI formats, and a future -version of this man page will describe the converged result. -Efforts to aid this convergence are encouraged. -.SS Security -A URI does not in itself pose a security threat. -There is no general guarantee that a URL, which at one time -located a given resource, will continue to do so. -Nor is there any -guarantee that a URL will not locate a different resource at some -later point in time; such a guarantee can be -obtained only from the person(s) controlling that namespace and the -resource in question. -.P -It is sometimes possible to construct a URL such that an attempt to -perform a seemingly harmless operation, such as the -retrieval of an entity associated with the resource, will in fact -cause a possibly damaging remote operation to occur. -The unsafe URL -is typically constructed by specifying a port number other than that -reserved for the network protocol in question. -The client unwittingly contacts a site that is in fact -running a different protocol. -The content of the URL contains instructions that, when -interpreted according to this other protocol, cause an unexpected -operation. -An example has been the use of a gopher URL to cause an -unintended or impersonating message to be sent via a SMTP server. -.P -Caution should be used when using any URL that specifies a port -number other than the default for the protocol, especially when it is -a number within the reserved space. -.P -Care should be taken when a URI contains escaped delimiters for a -given protocol (for example, CR and LF characters for telnet -protocols) that these are not unescaped before transmission. -This might violate the protocol, but avoids the potential for such -characters to be used to simulate an extra operation or parameter in -that protocol, which might lead to an unexpected and possibly harmful -remote operation to be performed. -.P -It is clearly unwise to use a URI that contains a password which is -intended to be secret. -In particular, the use of a password within -the "userinfo" component of a URI is strongly recommended against except -in those rare cases where the "password" parameter is intended to be public. -.SH BUGS -Documentation may be placed in a variety of locations, so there -currently isn't a good URI scheme for general online documentation -in arbitrary formats. -References of the form -<file:///usr/doc/ZZZ> don't work because different distributions and -local installation requirements may place the files in different -directories -(it may be in /usr/doc, or /usr/local/doc, or /usr/share, -or somewhere else). -Also, the directory ZZZ usually changes when a version changes -(though filename globbing could partially overcome this). -Finally, using the file: scheme doesn't easily support people -who dynamically load documentation from the Internet (instead of -loading the files onto a local filesystem). -A future URI scheme may be added (e.g., "userdoc:") to permit -programs to include cross-references to more detailed documentation -without having to know the exact location of that documentation. -Alternatively, a future version of the filesystem specification may -specify file locations sufficiently so that the file: scheme will -be able to locate documentation. -.P -Many programs and file formats don't include a way to incorporate -or implement links using URIs. -.P -Many programs can't handle all of these different URI formats; there -should be a standard mechanism to load an arbitrary URI that automatically -detects the users' environment (e.g., text or graphics, -desktop environment, local user preferences, and currently executing -tools) and invokes the right tool for any URI. -.\" .SH AUTHOR -.\" David A. Wheeler (dwheeler@dwheeler.com) wrote this man page. -.SH SEE ALSO -.BR lynx (1), -.BR man2html (1), -.BR mailaddr (7), -.BR utf\-8 (7) -.P -.UR http://www.ietf.org\:/rfc\:/rfc2255.txt -IETF RFC\ 2255 -.UE |