specified</a></li>
<li><a href="#formatting">Controlling other formatting options</a></li>
<li><a href="#misc">Miscellaneous option modifiers</a></li>
+ <li><a href="#response">Response files</a></li>
</ul></li>
<li><a href="#toplevel">Top-Level Classes and Functions</a>
example, consider <tt>gcc</tt>'s <tt>-x LANG</tt> option. This tells
<tt>gcc</tt> to ignore the suffix of subsequent positional arguments and force
the file to be interpreted as if it contained source code in language
- <tt>LANG</tt>. In order to handle this properly , you need to know the
+ <tt>LANG</tt>. In order to handle this properly, you need to know the
absolute position of each argument, especially those in lists, so their
interaction(s) can be applied correctly. This is also useful for options like
<tt>-llibname</tt> which is actually a positional argument that starts with
initial value. (You will get an error at runtime if you don't put them in
the right order.)</li>
-<li><a name="cl::location">The <b><tt>cl::location</tt></b></a> attribute where to
-store the value for a parsed command line option if using external storage. See
-the section on <a href="#storage">Internal vs External Storage</a> for more
+<li><a name="cl::location">The <b><tt>cl::location</tt></b></a> attribute where
+to store the value for a parsed command line option if using external storage.
+
See the section on <a href="#storage">Internal vs External Storage</a> for more
information.</li>
<li><a name="cl::aliasopt">The <b><tt>cl::aliasopt</tt></b></a> attribute
You will get a compile time error if you try to use cl::values with a parser
that does not support it.</li>
+<li><a name="cl::multi_val">The <b><tt>cl::multi_val</tt></b></a>
+attribute specifies that this option takes has multiple values
+(example: <tt>-sectalign segname sectname sectvalue</tt>). This
+attribute takes one unsigned argument - the number of values for the
+option. This attribute is valid only on <tt>cl::list</tt> options (and
+will fail with compile error if you try to use it with other option
+types). It is allowed to use all of the usual modifiers on
+multi-valued options (besides <tt>cl::ValueDisallowed</tt>,
+obviously).</li>
+
</ul>
</div>
error. As with <b><tt>cl::CommaSeparated</tt></b></a>, this modifier
only makes sense with a <a href="#cl::list">cl::list</a> option.</li>
-
</ul>
<p>So far, these are the only three miscellaneous option modifiers.</p>
</div>
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+ <a name="response">Response files</a>
+</div>
+
+<div class="doc_text">
+
+<p>Some systems, such as certain variants of Microsoft Windows and
+some older Unices have a relatively low limit on command-line
+length. It is therefore customary to use the so-called 'response
+files' to circumvent this restriction. These files are mentioned on
+the command-line (using the "@file") syntax. The program reads these
+files and inserts the contents into argv, thereby working around the
+command-line length limits. Response files are enabled by an optional
+fourth argument to
+<a href="#cl::ParseEnvironmentOptions"><tt>cl::ParseEnvironmentOptions</tt></a>
+and
+<a href="#cl::ParseCommandLineOptions"><tt>cl::ParseCommandLineOptions</tt></a>.
+</p>
+
+</div>
+
+
<!-- ======================================================================= -->
<div class="doc_subsection">
<a name="toplevel">Top-Level Classes and Functions</a>
<p>The <tt>cl::ParseCommandLineOptions</tt> function requires two parameters
(<tt>argc</tt> and <tt>argv</tt>), but may also take an optional third parameter
which holds <a href="#description">additional extra text</a> to emit when the
-<tt>--help</tt> option is invoked.</p>
+<tt>--help</tt> option is invoked, and a fourth boolean parameter that enables
+<a href="#response">response files</a>.</p>
</div>
href="#cl::ParseCommandLineOptions"><tt>cl::ParseCommandLineOptions</tt></a>
does.</p>
-<p>It takes three parameters: the name of the program (since <tt>argv</tt> may
+<p>It takes four parameters: the name of the program (since <tt>argv</tt> may
not be available, it can't just look in <tt>argv[0]</tt>), the name of the
-environment variable to examine, and the optional
+environment variable to examine, the optional
<a href="#description">additional extra text</a> to emit when the
-<tt>--help</tt> option is invoked.</p>
+<tt>--help</tt> option is invoked, and the boolean
+switch that controls whether <a href="#response">reponse files</a>
+should be read.</p>
<p><tt>cl::ParseEnvironmentOptions</tt> will break the environment
variable's value up into words and then process them using
<hr>
<address>
<a href="http://jigsaw.w3.org/css-validator/check/referer"><img
- src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
+ src="http://jigsaw.w3.org/css-validator/images/vcss-blue" alt="Valid CSS"></a>
<a href="http://validator.w3.org/check/referer"><img
- src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!"></a>
+ src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
<a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
<a href="http://llvm.org">LLVM Compiler Infrastructure</a><br>
projects / oota-llvm.git / blobdiff