and white space occurring before a directive are ignored, so
you may indent directives for clarity.</p>
- <p>The values of shell environment variables can be used in
- configuration file lines using the syntax <code>${ENVVAR}</code>.
- If "ENVVAR" is the name of a valid environment variable, the value
+ <p>The values of variables defined with the <code class="directive"><a href="./mod/core.html# define">
+ Define</a></code> of or shell environment variables can be used in
+ configuration file lines using the syntax <code>${VAR}</code>.
+ If "VAR" is the name of a valid variable, the value
of that variable is substituted into that spot in the
configuration file line, and processing continues as if that text
- were found directly in the configuration file. (If the ENVVAR
- variable is not found, the characters "${ENVVAR}" are left
- unchanged for use by later stages in the config file
- processing.)</p>
-
- <p>Only environment variables defined before the server is started
- can be used in expansions. Variables defined in the
- configuration file itself, for example with <code class="directive"><a href="./mod/mod_env.html#setenv">SetEnv</a></code>, take effect too late to be
- used for expansions in the configuration file.</p>
+ were found directly in the configuration file. Variables defined with
+ <code class="directive"><a href="./mod/core.html#define">Define</a></code> take precedence over shell
+ environment variables. If the "VAR" variable is not found, the characters
+ <code>${VAR}</code> are left unchanged, and a warning is logged. Variable
+ names may not contain colon ":" characters, to avoid clashes with
+ <code class="directive"><a href="./mod/mod_rewrite.html#rewritemap">RewriteMap</a></code>'s syntax.</p>
+
+ <p>Only shell environment variables defined before the server is started
+ can be used in expansions. Environment variables defined in the
+ configuration file itself, for example with <code class="directive"><a href="./mod/mod_env.html# setenv">
+ SetEnv</a></code>, take effect too late to be used for expansions in the
+ configuration file.</p>
<p>The maximum length of a line in the configuration file, after
- environment-variable substitution, joining any continued lines and
- removing leading and trailing white space, is 8192 characters.</p>
+ variable substitution, joining any continued lines and removing leading
+ and trailing white space, is 8192 characters.</p>
<p>You can check your configuration files for syntax errors
without starting the server by using <code>apachectl
and white space occurring before a directive are ignored, so
you may indent directives for clarity.</p>
- <p>The values of shell environment variables can be used in
- configuration file lines using the syntax <code>${ENVVAR}</code>.
- If "ENVVAR" is the name of a valid environment variable, the value
- of that variable is substituted into that spot in the
- configuration file line, and processing continues as if that text
- were found directly in the configuration file. (If the ENVVAR
- variable is not found, the characters "${ENVVAR}" are left
- unchanged for use by later stages in the config file
- processing.)</p>
-
- <p>Only environment variables defined before the server is started
- can be used in expansions. Variables defined in the
+ <p>The values of variables defined with the <directive
+ module="core">Define</directive> of or shell environment variables can
+ be used in configuration file lines using the syntax <code>${VAR}</code>.
+ If "VAR" is the name of a valid variable, the value of that variable is
+ substituted into that spot in the configuration file line, and processing
+ continues as if that text were found directly in the configuration file.
+ Variables defined with <directive module="core">Define</directive> take
+ precedence over shell environment variables.
+ If the "VAR" variable is not found, the characters <code>${VAR}</code>
+ are left unchanged, and a warning is logged.
+ Variable names may not contain colon ":" characters, to avoid clashes with
+ <directive module="mod_rewrite">RewriteMap</directive>'s syntax.</p>
+
+ <p>Only shell environment variables defined before the server is started
+ can be used in expansions. Environment variables defined in the
configuration file itself, for example with <directive
- module="mod_env">SetEnv</directive>, take effect too late to be
- used for expansions in the configuration file.</p>
+ module="mod_env">SetEnv</directive>, take effect too late to be used for
+ expansions in the configuration file.</p>
<p>The maximum length of a line in the configuration file, after
- environment-variable substitution, joining any continued lines and
- removing leading and trailing white space, is 8192 characters.</p>
+ variable substitution, joining any continued lines and removing leading
+ and trailing white space, is 8192 characters.</p>
<p>You can check your configuration files for syntax errors
without starting the server by using <code>apachectl
</IfDefine><br />
</code></p></div>
+ <p>Variable names may not contain colon ":" characters, to avoid clashes
+ with <code class="directive"><a href="../mod/mod_rewrite.html#rewritemap">RewriteMap</a></code>'s syntax.</p>
+
</div>
<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
<div class="directive-section"><h2><a name="Directory" id="Directory"><Directory></a> <a name="directory" id="directory">Directive</a></h2>
Define SSL<br/>
</IfDefine><br/>
</example>
+
+ <p>Variable names may not contain colon ":" characters, to avoid clashes
+ with <directive module="mod_rewrite">RewriteMap</directive>'s syntax.</p>
</usage>
</directivesynopsis>