1 10/02/85  Format of a Listin Segment
 2 
 3 The format of a listin segment consists of three parts--header,
 4 fields, and data records.
 5 
 6 The header contains several statements that give information about the
 7 records.  The statements are:
 8    Comment_delimiter: c;     or Cd: c;
 9    Field_delimiter: f;       or Fd: f;
10    Record_delimiter: r;      or Rd: r;
11    Field_names: fn1,...fnK; or Fn: fn1,...fnK;
12    Records:
13 
14 
15 The Comment_delimiter statement specifies the character(s) used to
16 delimit comments within the listin segment.  If you don't give it, no
17 comments are allowed.  The delimiter can either be "pl1", in which
18 case comments begin with "/*" and end with "*/", or a single character
19 chosen from the set !#$%&*=?@^|~, in which case that character is used
20 to begin and end a comment.  The Field_delimiter statement specifies
21 the character used to separate fields within a record; if you don't
22 supply it, the default is "=".  The Record_delimiter statement
23 specifies the character used to separate records; if you don't specify
24 it, the default is "$".  Record and field delimiters must be one
25 character long and must be from the set !#$%&*=?@^|~.  The Field_names
26 statement specifies all the field names that you can use in the listin
27 segment.  It is required.  Field names can be up to 32 characters
28 long, must begin with an alphabetic character, and otherwise must
29 contain only alphanumeric characters and underscores.
30 
31 
32 Everything after the end-of-the-header statement is taken to be record
33 information.  (The end-of-the-header statement is "Records:".)  Each
34 record must begin with a record delimiter.  Each field must begin with
35 a field delimiter.  Each field delimiter must be directly followed by
36 a field name.  The optional field value follows the field name,
37 separated by one or more white space characters (NL, SP, HT, NP, VT).
38 If leading and trailing white space is not to be removed from the
39 field value or if the field value contains record delimiter or field
40 delimiter characters, enclose the entire field value in quotes.  As in
41 PL/I, to enclose a quote character in a quoted string, double the
42 quote.
43 
44 
45 The fields contain the various types of information stored in a list
46 (e.g., first name, last name, street address, date of employment,
47 etc.).  Because data records are stored separately within a listin
48 file, give the field names with each data record.  Within a data
49 record, a field is specified by a field delimiter character followed
50 immediately by the field name (e.g., =lname).
51 
52 The data records (or records) contain the specific information
53 associated witht the subject of each record.  A record can contain
54 some or all of the fields defined in the header, and fields not
55 specified for a record are considered to be null.  Duplicate fields
56 are not allowed within a record.
57 
58 For related topics see lister.gi and listform_segment.gi; for examples
59 see the Multics WORDPRO Reference Manual (AZ98).