;'). Statements are composed of tokens
separated by white space, which can be any combination of blanks, tabs
and newlines. This structure simplifies identification of the parts
of the configuration associated with each other and with specific
protocols. Comments may be specified in either of two forms. One
form begins with a pound sign (`#') and runs to the end
of the line. The other form, C style, starts with a `/*'
and continues until it reaches `*/'.
[' and
`]') are used to show optional keywords and parameters.
The vertical bar (`|') is used to indicate between a
choice of optional parameters. Parentheses (`(' and
`)') are used to group keywords and parameters when
necessary. For example, in the syntax description:
[ backbone | ( area area ) ]
The square brakets say that either parameter is optional. The
keywords are backbone and area.
The vertical bar indicates that either ``backbone''
or ``area area'' may be specified. Since
area is in the variable definition style, it is
a parameter that needs to be provided.
Two other types of statements do not fit in these categories: %directive statements and %trace statements. These statements provide instructions to the parser and control tracing from the configuration file. They do not relate to the configuration of any protocol and may occur anywhere in the gated.conf file.