= Сообщение: 2484 из 3030 =================================== GANJANET.LOCAL = От : Mithgol the Webmaster 2:5063/88 14 Oct 07 00:21:54 Кому : All 14 Oct 07 00:21:54 Тема : [2/11] FidoURL.txt FGHI : area://GANJANET.LOCAL?msgid=2:5063/88+471129a6 На : area://GANJANET.LOCAL?msgid=2:5063/88+4711287a = Кодировка сообщения определена как: CP866 ================================== ============================================================================== * изначально написано в эхоконференцию FTSC_Public * также было отослано в эхоконференцию GanjaNet.Local * также было отослано в эхоконференцию Ru.Fido.WWW * также было отослано в эхоконференцию Ru.FTN.Develop * также было отослано в эхоконференцию SU.FidoTech * также было отослано в эхоконференцию Titanic.Best
textsection 2 of 11 of file FidoURL.txt textbegin.section
5.2.2. Encoding of octets -+-----------------------
The character sequences in different parts of a URL are used to represent sequences of octets.
It is possible to represent an octet by the chararacter which has that octet as its code within the pure 7-bit ASCII character set. However, there are some exceptions (see below).
Alternatively, octets MAY be encoded by a character triplet consisting of the character "%" followed by the two hexadecimal digits (from "0123456789ABCDEF") which form the hexadecimal value of the octet. (The characters "abcdef" MAY also be used in hexadecimal encodings.)
Hexadecimal encoding of any octet MAY be used even when it is not REQUIRED or RECOMMENDED. However, it is RECOMMENDED to avoid unnecessary hexadecimal encoding, thus keeping URLs reasonably short.
It is either REQIRED or RECOMMENDED to use the hexadecimal encoding of octets if they have no corresponding graphic character within the 7-bit ASCII character set, or if the use of the corresponding character is unsafe, or if the corresponding character is reserved for some other interpretation within the particular URL scheme. These requirements and recommendations are detailed below.
5.2.2.1. No corresponding graphic 7-bit character -+-----------------------------------------------
URLs are written only with the graphic printable characters of the 7-bit ASCII coded character set.
The octets 80-FF hexadecimal do not belong to 7-bit ASCII, and the octets 00-1F and 7F hexadecimal represent control characters; these octets MUST be encoded.
The space character is unsafe because significant spaces may disappear and insignificant spaces may be introduced when URLs are transcribed or typeset or subjected to the treatment of word-processing programs. The octet 20 hexadecimal MUST always be encoded.
The characters "<" and ">" are unsafe because they are used as the delimiters around tags in HTML hypertext and XML data. The octets 3C and 3E hexadecimal MUST always be encoded.
The quote mark (""") is used to delimit URLs in some systems, including valid XHTML and XML. The octet 22 hexadecimal MUST always be encoded.
The character "#" is unsafe because it is used in World Wide Web and in other systems to delimit a URL from a fragment or anchor identifier that might follow it. The octet 23 hexadecimal MUST always be encoded.
The character "%" is unsafe because it is used for encodings of other characters. The octet 25 hexadecimal MUST always be encoded.
The character sequence of triple minus ("-" repeated thrice) has a special meaning in Fidonet and can accidentally start a tearline in some cases (e.g. when a line is wrapped). At least one of the three corresponding octets (2D 2D 2D hexadecimal) MUST be encoded if they follow each other in a sequence.
Other characters were declared unsafe in RFC 1738 because some gateways and other transport agents were known to sometimes modify such characters. These characters are "{", "}", "|", "\", "^", "~", "[", "]", and "`". The corresponding octets (7B 7D 7C 5C 5E 7E 5B 5D 60 hexadecimal) MUST always be encoded for the sake of Internet compatibility.
All unsafe characters MUST always be encoded within a URL. For example, the character "#" MUST be encoded within URLs even in software programs that do not normally deal with fragment or anchor identifiers, so that if the URL is copied into another program that does use them, it will not be necessary to change the URL encoding.
Many URL schemes reserve certain characters for a special meaning: appearance of that characters in the scheme-specific part of the URL (in <scheme-specific-part> after scheme name) has a designated semantics.
Usually a URL has the same interpretation when an octet is represented by a character and when it is encoded. However, this is not true for reserved characters: encoding a character that is reserved for a particular scheme may cause harm to the meaning of a URL, if the character is used according to its designated semantics. And vice versa.
The character "?" is used as the delimiter between required and optional parts of the URL. The delimiter itself MUST NOT be encoded. If the character "?" appears in any other part of a URL, it MUST be encoded, so it won't be confused with the delimiter.
The character "=" is used as the delimiter between parameter names and parameter values. The delimiters themselves MUST NOT be encoded. If the character "=" appears in any other part of a URL, it MUST be encoded, so it won't be confused with any of the delimiters.
The character "&" is used as the delimiter between "parameter=value" pairs. The delimiters themselves MUST NOT be encoded. If the character "&" appears in any other part of a URL, it MUST be encoded, so it won't be confused with any of the delimiters.
The character "@" is used as the delimiter between an areatag and its FTN domain suffix (see subsection 5.2.2.3.1 for details). The delimiters themselves MUST NOT be encoded. If the character "@" appears inside the areatag itself (i.e. not between the areatag and its suffix), it MUST be encoded, though in any other part of an URL this character MAY be left as it is.
The character "/" is scheme-specific:
*) In some schemes ("netmail:", for example) the character "/" has its own (literal) meaning, as it is widely used in standard Fidonet addressing notation <zone>:<net>/<node>.<point> (see FSP-1004 for details).
*) In some other schemes the character "/" is reserved to be used in the file path (<directory>/<directory>/...<directory>/<filename>), and its corresponding octet (2F hexadecimal) MUST be encoded if it does not delimit parts of the path.
See the scheme-specific details below (in scheme sections).
5.2.2.3.1 Using domain suffixes in areatags -+-----------------------------------------
Different domains of Fidonet (in "@<domain>" sense, see FSP-1004 for details), also known as Fidonet Technology Networks, MAY have common echomail areas (i.e. areas that are gated between some of FTNs) and MAY have internal echomail areas (i.e. areas distributed only inside the domain).
If a Fidonet station has access to echomail areas in dirrerent domains, it MAY encounter areas of the same name (of the same areatag) in different FTN domains. It's OK if it is the same common area; however, even if they are different internal areas that just have the same name by coincidence, the Uniform Resource Locator MAY contain an optional "@<domain>" suffix after the areatag, and thus distinguish between different areas. The suffix contains the domain name of the FTN of the designated echo area and the preceding "@" symbol.
Domain suffixes are intentionally OPTIONAL, because FTNs generally have their own means to ensure that the names of echomail areas are unique. Some FTNs, for example, use their domain names as prefixes or suffixes for echomail area names (i.e. othernet.areaname, or areaname.othernet), thus eliminating the need of a special URL element, that otherwise would be needed for the same purpose.
The character "@" is a reserved character. When it is used as the delimiter between an areatag and its FTN domain name, the character "@" MUST NOT be encoded. However, if the character "@" appears inside the areatag itself (e.g. when the area name is something like SETI@home), then the character MUST be encoded, so it won't be confused with the delimiters.
But outside of the areatags the character "@" is not reserved, so it MAY be either encoded or left intact in any other part of the URL (e.g. in object's path, in parameter's name, in parameter's value, etc.).
5.2.2.4. The plus ("+") and the encoding of white spaces -+------------------------------------------------------
White spaces (octets 20 hexadecimal) are the most common unsafe characters in Fidonet, and so they play a significant role in some scheme-specific parts of the URL: they appear in MSGID kludges, they are used as delimiters between words in lines of text, etc.
To enhance human readability of Fidonet URLs, and to make them shorter, a new shorter synonym for "%20" hexadecimal triplet is available. It is the plus sign ("+").
Programs interpreting scheme-specific part of Fidonet URL MUST treat the character plus ("+") there as equivalent to the white space hexadecimal triplet ("%20").
Because of that, the plus character itself is reserved, and its own corresponding octet (2B hexadecimal) MUST be encoded if it appears in scheme-specific part of Fidonet URL.
The rule of equivalence between "+" and "%20" does not apply outside of the scheme-specific part of URL; the plus sign has no special meaning in scheme name, since white spaces are not allowed in scheme names.
5.2.2.4.2. Internet practice note -+-------------------------------
This practice is not documented in RFC 1738. It is, however, documented in RFC 1630.
5.2.2.5. URLs that span several lines of text in Fidonet -+------------------------------------------------------
Some Fidonet mail editors and other units of software do not permit lines of text to be longer than some limit, e.g. longer than 78 or 80 characters (or a lesser limit, especially inside quotes). If text is longer than limit, it spans several lines (usually a line break is inserted instead of a white space; however, if more than 80 successive characters do not contain white spaces, the line MAY be broken anyway. Or less than 80: the limit MAY vary.)
Sometimes it MAY become necessary for a long enough URL to span several lines as well. To distinguish between URLs that span several lines and URLs that just end (by chance) before some end of line, a special mark is needed.
Two successive "%" characters MUST NOT appear in URLs (because "%" MUST be followed by two hexadecimal digits), and they are also rare in ordinary text. That's why "%%" character sequence MUST be used before and after a line break in URL, to mark that the line break does not end the URL.
If an URL parser encounters "%%" character sequence in the URL it parses, then the parser MUST skip the "%%" sequence, and all characters after it and before the line break, and the line break, and all characters after the line break and before the next "%%" sequence, and that "%%" sequence. Then the URL continues.
Quote decoration MAY be encountered after the line break and before the "%%" sequence marking the place where the URL resumes. Fidonet mail editors MAY rearrange the "%%" sequences and line breaks when quoting the quotes.
Example:
MtW>> To track Fidonet software development in Russian, MtW>> a newsreel like area://Ru.FTN.Develop+Ru.FTN.Win%% MtW>> %%Soft+Ru.FIPS/ is often used.
MtW>>>>> To track Fidonet software development in Russian, MtW>>>>> a newsreel like area://Ru.FTN.Develop+Ru.FTN.W%% MtW>>>>> %%inSoft+Ru.FIPS/ is often used.
(the meaning of area:// URLs is explained in section 7.2)
Frame decoration MAY be encountered after the line break and before the "%%" sequence marking the place where the URL resumes, or before the line break and after the "%%" sequence marking the place where the URL pauses.
Example:
+==========================================================+ + + + To track Fidonet software development in Russian, + + a newsreel like area://Ru.FTN.Develop+Ru.FTN.Win%% + + %%Soft+Ru.FIPS/ is often used. + + + +==========================================================+
Any other decoration is also possible, so the URL parser MUST expect it. For example, the URL parser MUST allow more than one line break between the URL-pausing "%%" and the next "%%", because additional line breaks MAY be introduced by quoting.
Example:
*********************************************************** *********************************************************** ** ** ** ATTENTION! Grab the N5019 pointlist at fecho://p%% ** ** %%ntlist/pnt5019.zip ** ** ** *********************************************************** ***********************************************************
(the meaning of fecho:// URLs is explained in section 7.4)
textend.section
With best Fidonet 2.0 regards, Mithgol the Webmaster. [Real nodelisted name: Sergey Sokoloff]
... Never judge an iBook by its cover. (Bugzilla Quip System) --- Come with me in the twilight of a summer night for a while... .hack//SIGN * Origin: Be careful, the paranoid ones are always wathing you!.. (2:5063/88)
