1、Standard ECMA-208December 1994Standardizing Information and Communication SystemsPhone: +41 22 849.60.00 - Fax: +41 22 849.60.01 - ECMANEWS: +41 22 735.33.29 - Internet: HelpdeskECMA.CHSystem-Independent DataFormatStandard ECMA-208December 1994Standardizing Information and Communication SystemsPhone
2、: +41 22 849.60.00 - Fax: +41 22 849.60.01 - ECMANEWS: +41 22 735.33.29 - Internet: HelpdeskECMA.CHMB - ECMA-208.DOC - 07.04.95 12,11System-Independent DataFormat(SIDF)Brief HistoryThe System Independent Data Format Association (SIDF) was formed in early 1993 by a consortium of industries.ECMA TC15
3、adopted the work of this committee in early 1994. The document was transformed into an ECMA Standard byECMA TC15.It is contributed to ISO/IEC JTC 1 for adoption as an International Standard under the fast-track procedure.This ECMA Standard has been adopted by the ECMA General Assembly of December 19
4、94.- i -Table of contentsPageSection 1 - General 11 Scope 12 Conformance 12.1 Conformance of Media Volumes 12.2 Conformance of an originating system 12.3 Conformance of a receiving system 13 References 14 Definitions 14.1 Blank Space 14.2 byte 14.3 Byte Sequence 24.4 Field 24.5 Field Identifier (FID
5、) 24.6 Field Table 24.7 File 24.8 file mark 24.9 File Set 24.10 Interleaved File Sets 24.11 Iterated Field Set 24.12 operating system 24.13 originating system 24.14 Relative Byte Position 24.15 receiving system 24.16 Sector 24.17 Sector Number 24.18 Source 34.18 standard for recording 34.20 Volume 3
6、4.21 Volume Set 34.22 Volume Set Sequence Number 35 General conventions and notations 35.1 Representation of numbers 35.2 Names 35.3 Structures 35.4 Fields 35.5 Field Identifiers (FIDs) 35.6 Field Tables 35.7 Headers 35.8 Indices 45.9 Structure description schema 4- ii -Section 2 - Requirements for
7、the media 56 Specific conventions and notations for the recorded format 56.1 Recording of numbers 56.2 Character sets and coding 56.3 Character set specification (CHAR SPEC) 56.3.1 Character Set Type 56.3.2 Character Set Information 66.4 CS0 character set 66.5 CS1 character set 66.6 CS2 character se
8、t 66.7 CS3 character set 66.8 CS4 character set 66.9 CS5 character set 66.10 CS6 character set 66.11 CS7 character set 66.11.1 Code extension characters 66.12 CS8 character set 76.13 Source Name Space specification 76.13.1 Name Space 76.14 NS0 Name Space 86.15 NS1 Name Space 86.16 NS2 Name Space 86.
9、17 NS3 Name Space 96.18 NS4 Name Space 96.19 NS5 Name Space 96.20 NSFC Name Space 106.21 NSFE Name Space 106.22 Strings 106.23 Resynchronization Pattern 107 Timestamp 107.1 Type and Time Zone (RBP 0) 107.2 Year (RBP 2) 117.3 Month (RBP 4) 117.4 Day (RBP 5) 117.5 Hour (RBP 6) 117.6 Minute (RBP 7) 117
10、.7 Second (RBP 8) 117.8 Centiseconds (RBP 9) 117.9 Hundreds of microseconds (RBP 10) 117.10 Microseconds (RBP 11) 118 Requirements for a standard for recording 119 Cyclic Redundancy Check (CRC) 1210 Organization of Information on a Volume 1210.1 Recording of Sectors 12- iii -10.2 Organization of a V
11、olume 1210.3 Volume Sets 1210.4 Recording of Fields 1410.4.1 Null Field 1410.5 Recording of Field Tables 1410.6 Recording of Buffers 1410.7 Recording of file marks 1511 Organization of Information within a File Set 1511.1 Organization of a File Set 1511.2 File Sets spanning multiple Volumes 1711.3 I
12、nterleaving 1712 Organization of information within a File 1813 Field Table description 1813.1 Volume Header Field Table 1913.2 Volume Trailer Field Table 2013.3 Blank Space Field Table 2113.4 Buffer Header Field Table 2113.5 Volume Index Field Table 2313.6 Volume Subindex Field Table 2413.7 File Se
13、t Header Field Table 2413.8 File Set Continuation Header Field Table 2713.9 File Set Trailer Field Table 2713.10 File Set Index Field Table 2813.11 File Set Subindex Field Table 3113.12 File Header Field Table 3113.13 File Continuation Header Field Table 3113.14 File Information Field Table 3213.15
14、File Data 3313.15.1 Path Field Table 3313.15.2 Characteristics Field Table 3313.15.3 Source volume File Data 3413.15.4 Source directory File Data 3513.15.5 Source file File data 3613.15.6 Transaction Set File data 3713.15.7 Streams 3813.16 Levels of partition interchange 4113.16.1 Level 1 of partiti
15、on interchange 4113.16.2 Level 2 of partition interchange 4114 Requirements for systems 4114.1 Requirements for the description of systems 4114.2 Requirements for an originating system 4114.2.1 General 4114.2.2 Mandatory access by user 4114.2.3 Optional access by user 4114.2.4 Volume characteristics
16、 4214.2.5 File Set characteristics 42- iv -14.2.6 Recording of Bit Data 4214.2.7 Cyclic Redundancy Check (CRC) 4214.3 Requirements for a receiving system 4314.3.1 General 4314.3.2 Levels of conformance 43Annex A - Structure of the Field Identifier 45Annex B - Field Data Length Structure 49Annex C -
17、Field specification 51Annex D - Numerical List of the Field Identifiers specified by this ECMA Standard 81Annex E - Numerical List of Field Identifiers which are deprecated or not specified by this ECMA Standard 89Section 1 - General1 ScopeThis ECMA Standard specifies a logical format for informatio
18、n interchange and secondary data storage. The formatprovides a system-independent data format (SIDF) for the representation of primary file system information. Thisinformation includes, among other things, data, attributes and characteristics. This ECMA Standard specifies the organization of the inf
19、ormation on target media, requirements for originating and receiving systems for the processing of the information.2 Conformance2.1 Conformance of Media VolumesA Volume shall be in conformance with this ECMA Standard if all information recorded on it meets the relevantrequirements of sections 2 and
20、3 for the Level of partition claimed.2.2 Conformance of an originating systemAn originating system shall be in conformance with this ECMA Standard if it meets the requirements of 14.2.2.3 Conformance of a receiving systemA receiving system shall be in conformance with this ECMA Standard if it meets
21、the requirements of 14.3 for theLevel of conformance claimed.3 ReferencesECMA-6 (1991) 7-bit Coded Character SetECMA-35 (1994) Code Extension TechniquesECMA-94 (1986) 8-Bit Single-Byte Coded Graphic Character Sets - Latin Alphabets No. 1 to No. 4ECMA-119 (1987) Volume and File Structure of CD-ROM fo
22、r Information InterchangeECMA-167 (1994) Volume and File Structure of Write-Once and Rewritable Media using Non-SequentialRecording for Information InterchangeISO/IEC 9945-1:1990, Information technology - Portable operating system interface (POSIX) - Part 1: SystemApplication Program Interface (API)
23、 C LanguageISO/IEC 10646-1:1993, Information technology - Universal multiple octet coded character set (UCS) - Part 1:Architecture and basic multilingual plane.ISO/IEC 13800:1995, Information technology - Procedure for the registration of identifiers and attributes for volumeand file structure.ITU R
24、ec. X.25: Interface between Data Terminal Equipment (DTE) and Data Circuit-Terminating Equipment (DCE)for Terminals operating in the Packet Mode and connected to Public Data Networks by dedicated Circuits.4 DefinitionsFor the purposes of this ECMA Standard, the following definitions apply.4.1 Blank
25、SpaceEither one or more NULL Fields, or a BLANK SPACE Field Table.4.2 byteA string of eight binary digits operated upon as a unit.- 2 -4.3 Byte SequenceAn ordered set of bytes.4.4 FieldThe basic logical grouping of data.4.5 Field Identifier (FID)A Byte Sequence which identifies a Field.4.6 Field Tab
26、leA set of logically associated Fields.4.7 FileA collection of data that is stored as a single unit. A File contains a representation of a single primary file systementity, such as a Source directory, file, data base object, or data base.4.8 file markA sector containing a control block used as a del
27、imiter to facilitate positioning, as defined by the relevant standardfor recording.NOTESome media may not support file marks.4.9 File SetA set of associated Files, sourced from a single Source, recorded within a Volume Set.4.10 Interleaved File SetsTwo or more File Sets are interleaved if any part o
28、f at least one is recorded between any parts of another.4.11 Iterated Field SetA sequence of one or more Fields, which may be repeated within a Field Table.4.12 operating systemThe software which controls the file system of the Source.4.13 originating systemAn information processing system which can
29、 create a File Set in a Volume Set for the purpose of data interchangewith another system.4.14 Relative Byte PositionIndicates the byte position in a number.4.15 receiving systemAn information processing system which can process a File Set of a Volume Set which has been created by anothersystem for
30、the purpose of data interchange.4.16 SectorThe data field of the smallest addressable part of the medium that can be accessed independently of otheraddressable parts of the medium.NOTEThis Sector is different from the physical sectors of a physical track.4.17 Sector NumberThe ordinal sequence number
31、 of a Sector within a Volume, starting with 0 (0, 1, 2, 3, ., n).- 3 -4.18 SourceThe primary system (e.g. file system, data base) which is the source of the Files that are recorded as a File Set forsecondary storage. The name of the Source is specified for the File Set, and is not included in the So
32、urce pathinformation of the individual Files.4.19 standard for recordingA standard that specifies the recording method and the addressing method for the information recorded on amedium.4.20 VolumeA set of Sectors which resides within one physical partition on a secondary storage medium.4.21 Volume S
33、etOne Volume, or multiple logically related Volumes.4.22 Volume Set Sequence NumberThe ordinal sequence number of each Volume within a Volume Set, starting with 1 (1, 2, 3, ., n).5 General conventions and notations5.1 Representation of numbers Numbers in decimal notation are shown as decimal digits.
34、 Numbers in hexadecimal notation are shown as a sequence of hexadecimal digits preceded by #. The setting of bits is denoted by ZERO or ONE. Numbers in binary notation and bit combinations are represented by sequences of ZEROs or ONEs. Bit combinations are shown with the most significant bit to the
35、left. Bits are indicated with the small letter b. Bytes are indicated with the capital letter B.5.2 NamesThe names of formally defined entities, such as a Volume, are shown with a capital initial.The name of Fields, such as VOLUME HEADER, are written in capitals.5.3 StructuresData structures are sho
36、wn in tables indicating the Relative Byte Position (RBP), purpose and size of the entities thatcomprise the structure.5.4 FieldsFields are denoted by names shown in capital letters.5.5 Field Identifiers (FIDs)A Byte Sequence in hexadecimal notation uniquely identifying a Field.5.6 Field TablesThe na
37、me of a Field Table is that of its first Field, it is shown with capital initials. Field Tables list each Field withits name, its FID and a brief description of the data. The normative definition of each Field is specified in annex C.The Data Description reads “empty“ if no Data part is included in
38、the Field. Iterated Field Sets within a Field Tableare shown indented, with a bar alongside. Nested Iterated Field Sets are shown with each inner level of nestingfurther indented than the outer level(s).5.7 HeadersThe term “File Set (Continuation) Header“ is used to express: File Set Header and/or F
39、ile Set Continuation Header.The term “File Record (Continuation) Header“ is used to express: File Record Header and/or File RecordContinuation Header.- 4 -5.8 IndicesThe term “Volume (Sub)Index“ is used to express: Volume Index and/or Volume Subindex. The term “File Set(Sub)Index“ is used to express
40、: File Set Index and/or File Set Subindex.5.9 Structure description schemaRequirements for recording the different elements of the format are summarized by means of a structuredescription.A structure shall be a sequence of terms. A term shall be either: a name, enclosed by , followed by a definition
41、 enclosed by , or a name, enclosed by , of a term defined in the structure or of a descriptor defined elsewhere in this ECMAStandard in the text associated with the structure.Within a definition enclosed by , the Or Operator and Repetition Operators may be applied to the terms therein.The Or Operato
42、r is represented by the character VERTICAL LINE: . It is placed between the terms to which itapplies and indicates that either term, but not both simultaneously, is valid at that point in the definition.There are three Repetition Operators, which shall be interpreted as shown in figure 1, where n an
43、d m are decimaldigits.Repetition Operator Interpretationnn+n+mn occurrences of the preceding termn or more occurrences of the preceding termn to m occurrences of the preceding termFigure 1 - Repetition OperatorsThe Repetition Operators shall apply only to the preceding term.The operators are listed
44、in increasing order of precedence:| repetition operator ( )Higher precedence operators shall be applied before lower precedence operators.As an example, the schema shown in figure 2 specifies that the entity “Concert“ shall be organized as zero or oneIntroduction, followed by one or more Pieces, an
45、Intermission, one or more Pieces, and zero or more Encores. APiece consists either of one Song or three to five Movements.Concert 0+1Piece | 3+5 1+1+0+Figure 2 - Example of the syntax of the structure description schema- 5 -Section 2 - Requirements for the media6 Specific conventions and notations f
46、or the recorded format6.1 Recording of numbers In each Field the information is recorded so that the least significant byte (denoted byte B0) is recorded first.Within each byte the least significant bit is denoted bit b0, the most significant bit is denoted b5, and is recordedfirst. This order of re
47、cording also applies to the data input of the cyclic redundancy code (CRC) and to itsoutput (CRC bits). Negative values are recorded in TWOs complement notation.6.2 Character sets and codingExcept as specified in this clause and in 6.13, the characters used in the Fields specified by this ECMA Stand
48、ardshall be coded according to the International Reference Version (IRV) of ECMA-6. The CS4 character setdescribed in 6.8 shall be the default character set, and shall be used if no other is explicitly specified. Thespecification of the characters allowed in these Fields and the method of recording
49、shall be recorded as a CHARSPEC Field (see 6.3).NOTESupport for a variety of character sets is a requirement of this ECMA Standard. Ideally, there should be only onecharacter standard used. In practice, several standards, including ECMA-6, ECMA-35, ECMA-94 and ISO/IEC10646-1 are used. This ECMA Standard accommodates current practice by specifying several character sets andproviding a mechanism for specifying other character sets.As an example, CS2 (see 6.6) uses the IRV of ECMA-6 as the basic character set but restr
