AS ISO 28500:2018 pdf free
AS ISO 28500:2018 pdf free.Information and documentation – WARC file format
A WARC format file is the simple concatenation of one or more WARC records. The first record usually describes the records to follow. In general, record content is either the direct result of a retrieval attempt (web pages, inline images, URL redirection information, DNS hostname lookup results, stand-alone files, etc. or is synthesized material (e.g. metadata, transformed content) that provides additional information about archived content.
A WARC record shall consist of a record header followed by a record content block and two new lines.The WARC record header shall consist of one first line declaring the record to be in the WARC format with a given version number, then a variable number of line-oriented named fields terminated by a blank line. The WARC record header format shall follow the general rules of HTTP/1.1 [RFC2616] and [RFC5322] headers with one major exception: it shall also allow UTF-8 characters, as specified in [RFC3629].
The top-level view of a WARC file can be expressed in an ABNF grammar, reusing the augmented constructs defined in section 2.1 of HTTP/1.1 [RFC2616]. (In particular, note that to avoid the risk of confusion, where any WARC rule has the same name as an [RFC2616] rule, the definition here has been made the same, except in the case of the CHAR rule, which in WARC includes multibyte UTF-8 characters.)
The WARC record relies heavily on named fields. Each named field consists of a name followed by a colon (“:”) and the field value. Field names are not case-sensitive. The field value may be preceded by any amount of linear white space (LWS), though a single space is preferred. Header fields can be extended over multiple lines by preceding each extra line with at least one space or tab character.
Named fields may appear in any order and field values may contain any UTF-8 character. Both defined-fields and extension-fields follow the generic named-field format. Extension-fields may be used in extensions of the core format.AS ISO 28500 pdf free download.
