The document-type declaration (DOCTYPE) identifies the source file document type and the rules the source file must follow.

>>-<!DOCTYPE--DM--SYSTEM--+---------------------------+-->-----><
                          +-[--entity-declarations--]-+      
                          '-(--entity-declarations--)-'      

DOCTYPE

Indicates that this is a document-type declaration.

DM

Indicates that this is a DTL source file defining dialog elements.

SYSTEM

Indicates that the rules for the DOCTYPE are contained in an external file.

[ | (

Indicates the beginning of the declaration subset. Either the left bracket or the open parenthesis can be used to begin the declaration subset. The declaration subset can contain entity declarations and parameter entity references. If the left bracket is coded, it must be the value X'AD'.

entity-declarations

The entity declarations you define for the source file must be coded within the declaration subset. Entity declarations contains a complete description of entity declarations.

] | )

Indicates the end of the declaration subset. Either the right bracket or the close parenthesis can be used to end the declaration subset. If the right bracket is coded, it must be the value X'BD'.