Document record, if present.
@item
-Any records not explicitly included in this list, in any order.
+Extension (type 7) records, in ascending numerical order of their
+subtypes.
@item
Dictionary termination record.
@table @code
@item char rec_type[4];
-Record type code, set to @samp{$FL2}.
+Record type code, set to @samp{$FL2}, that is, either @code{24 46 4c
+32} if the file uses an ASCII-based character encoding, or @code{5b c6
+d3 f2} if the file uses an EBCDIC-based character encoding.
@item char prod_name[60];
Product identification string. This always begins with the characters
@end multitable
@end quotation
+A few system files have been observed in the wild with invalid
+@code{write} fields, in particular with value 0. Readers should
+probably treat invalid @code{print} or @code{write} fields as some
+default format.
+
@node Value Labels Records
@section Value Labels Records
Machine endianness. 1 indicates big-endian, 2 indicates little-endian.
@item int32 character_code;
-@anchor{character-code}
-Character code. 1 indicates EBCDIC, 2 indicates 7-bit ASCII, 3
-indicates 8-bit ASCII, 4 indicates DEC Kanji.
-Windows code page numbers are also valid.
-
-Experience has shown that in many files, this field is ignored or incorrect.
-For a more reliable indication of the file's character encoding
-see @ref{Character Encoding Record}.
+@anchor{character-code} Character code. The following values have
+been actually observed in system files:
+
+@table @asis
+@item 1
+EBCDIC.
+
+@item 2
+7-bit ASCII.
+
+@item 1250
+The @code{windows-1250} code page for Central European and Eastern
+European languages.
+
+@item 1252
+The @code{windows-1252} code page for Western European languages.
+
+@item 28591
+ISO 8859-1.
+
+@item 65001
+UTF-8.
+@end table
+
+The following additional values are known to be defined:
+
+@table @asis
+@item 3
+8-bit ``ASCII''.
+
+@item 4
+DEC Kanji.
+@end table
+
+Other Windows code page numbers are known to be generally valid.
+
+Old versions of SPSS for Unix and Windows always wrote value 2 in this
+field, regardless of the encoding in use. Newer versions also write
+the character encoding as a string (see @ref{Character Encoding
+Record}).
@end table
@node Machine Floating-Point Info Record
@itemize @bullet
@item
-The set's name (an identifier that begins with @samp{$}).
+The set's name (an identifier that begins with @samp{$}), in mixed
+upper and lower case.
@item
An equals sign (@samp{=}).
A space.
@item
-The names of the variables in the set, each separated from the
-previous by a single space.
+The short names of the variables in the set, converted to lowercase,
+each separated from the previous by a single space.
@item
A line feed (byte 0x0a).
Continuous Scale
@end table
-SPSS 14 sometimes writes a @code{measure} of 0. PSPP interprets this
-as nominal scale.
+SPSS 14 sometimes writes a @code{measure} of 0 for string variables.
+PSPP interprets this as nominal scale.
@item int32 width;
The width of the display column for the variable in characters.
The total number of bytes in @code{encoding}.
@item char encoding[];
-The name of the character encoding. Normally this will be an official IANA characterset name or alias.
+The name of the character encoding. Normally this will be an official
+IANA character set name or alias.
See @url{http://www.iana.org/assignments/character-sets}.
+Character set names are not case-sensitive, but SPSS appears to write
+them in all-uppercase.
@end table
-This record is not present in files generated by older software.
-See also @ref{character-code}.
+This record is not present in files generated by older software. See
+also the @code{character_code} field in the machine integer info
+record (@pxref{character-code}).
+
+When the character encoding record and the machine integer info record
+are both present, all system files observed in practice indicate the
+same character encoding, e.g.@: 1252 as @code{character_code} and
+@code{windows-1252} as @code{encoding}, 65001 and @code{UTF-8}, etc.
+
+If, for testing purposes, a file is crafted with different
+@code{character_code} and @code{encoding}, it seems that
+@code{character_code} controls the encoding for all strings in the
+system file before the dictionary termination record, including
+strings in data (e.g.@: string missing values), and @code{encoding}
+controls the encoding for strings following the dictionary termination
+record.
@node Long String Value Labels Record
@section Long String Value Labels Record
In record type 18, this field contains a sequence of one or more
variable attribute sets. If more than one variable attribute set is
present, each one after the first is delimited from the previous by
-@code{/}. Each variable attribute set consists of a variable name,
+@code{/}. Each variable attribute set consists of a long
+variable name,
followed by @code{:}, followed by an attribute set with the same
syntax as on record type 17.
projects / pspp / blobdiff