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<H2>BIND Configuration File Guide--Comment Syntax</H2>

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<A NAME="Syntax"><H3>Syntax</H3></A>

<PRE>
/* This is a BIND comment as in C */

// This is a BIND comment as in C++

# This is a BIND comment as in common Unix shells and perl
</PRE>

<A NAME="Usage"><H3>Definition and Usage</H3></A>

<P>Comments may appear anywhere that whitespace may appear in a BIND
configuration file.</P>

<P>C-style comments start with the two characters <CODE>/*</CODE>
(slash, star) and end with <CODE>*/</CODE> (star, slash).  Because
they are completely delimited with these characters, they can be used
to comment only a portion of a line or to span multiple lines.</P>

<P>C-style comments cannot be nested.  For example, the following is
not valid because the entire comment ends with the first
<CODE>*/</CODE>:

<PRE>
/* This is the start of a comment.
   This is still part of the comment.
/* This is an incorrect attempt at nesting a comment. */
   This is no longer in any comment. */
</PRE>


<P>C++-style comments start with the two characters <CODE>//</CODE>
(slash, slash) and continue to the end of the physical line.  They
cannot be continued across multiple physical lines; to have one
logical comment span multiple lines, each line must use the
<CODE>//</CODE> pair.  For example:

<PRE>
// This is the start of a comment.  The next line
// is a new comment, even though it is logically
// part of the previous comment.
</PRE>

<P>Shell-style (or perl-style, if you prefer) comments start with the
character <CODE>#</CODE> (hash or pound or number or octothorpe or
whatever) and continue to the end of the physical line, like C++
comments.</P>  For example:

<PRE>
# This is the start of a comment.  The next line
# is a new comment, even though it is logically
# part of the previous comment.
</PRE>

<P><STRONG>WARNING:</STRONG> you cannot use the <CODE>;</CODE>
(semicolon) character to start a comment such as you would in a zone
file.  The semicolon indicates the end of a configuration statement,
so whatever follows it will be interpreted as the start of the next
statement.</P>

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