texinfo: Info Format Specification

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Appendix F Info Format Specification
************************************

Here we describe the technical details of the Info format.

  This format definition was written some 25 years after the Info format
was first devised.  So in the event of conflicts between this definition
and actual practice, practice wins.  It also assumes some general
knowledge of Texinfo; it is meant to be a guide for implementors rather
than a rigid technical standard.  We often refer back to other parts of
this manual for examples and definitions, rather than redundantly
spelling out every detail.

  In this formal description, the characters '<>*()|=#' are used for the
language of the description itself.  Other characters are literal.  The
formal constructs used are typical: '<...>' indicates a metavariable
name, '=' means definition, '*' repetition, '?' optional, '()' grouping,
'|' alternation, '#' comment.  Exception: '*' at the beginning of a line
is literal.

  We specify literal parentheses (those that are part of the Info
format) with <lparen> and <rparen>, meaning the single characters '('
and ')' respectively.

  Finally, the two-character sequence '^X' means the single character
'CTRL-X', for any X.

General

Info Format General Layout.

Text

Info Format Text Constructs.