#appinfo

A pre-defined, read-only shelf that provides processing data to an application by accessing the #appinfo parameter of an SGML declaration. It may appear only in a string expression, either in the format item "%g" or as the name of a stream.

Whether the #appinfo shelf has a value depends on the state of SGML parsing. It has a value only if the SGML declaration has already been parsed and it had an #appinfo declaration other than "None". If this is not the case, the stream is unattached.

Therefore, it is never attached in:

• a document-start rule.
• a do sgml-parse rule prior to the parse continuation operator (%c or suppress), unless a pre-compiled DTD is used.
• a do sgml-parse rule after the parse continuation operator (%c or suppress).
• a document-end rule when errors occurred before this information could be determined.

In addition, use of #appinfo has the following limitations:

• It cannot be opened, closed, written to, or discarded.
• It is not "attached" if an SGML declaration was not given, "appinfo none" was specified in the SGML declaration, or it is used in a cross-translation.
• If it is "attached" it is also "closed".

#appinfo is "read-only" and may be passed to a function only as a read-only argument, remainder, or value.

#appinfo must not be accessed in process, process-start or process-end rules.