From: cuz <cuz@b7a2c559-68d2-44c3-8de9-860c34a00d81>
Date: Fri, 8 Dec 2000 15:47:25 +0000 (+0000)
Subject: Describe initialized void variables
X-Git-Tag: V2.12.0~2973
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=b2b7fb4b3353d0fc604ab70bcba669f3fe1ee868;p=cc65

Describe initialized void variables


git-svn-id: svn://svn.cc65.org/cc65/trunk@569 b7a2c559-68d2-44c3-8de9-860c34a00d81
---

diff --git a/doc/cc65.sgml b/doc/cc65.sgml
index 42b2b0be3..234ce16f8 100644
--- a/doc/cc65.sgml
+++ b/doc/cc65.sgml
@@ -429,6 +429,32 @@ This cc65 version has some extensions to the ISO C standard.
 	The macro will print the name of the current function plus a given
 	string.
 	<p>
+
+<item> 	cc65 allows the initialization of <tt/void/ variables. This may be 
+	used to create variable structures that are more compatible with 
+	interfaces written for assembler languages. Here is an example:
+
+	<tscreen><verb>
+	void GCmd = {	(char)3, (unsigned)0x2000, (unsigned)0x3000 };
+	</verb></tscreen>
+
+	This will be translated as follows:
+
+	<tscreen><verb>
+	_GCmd:
+	 	.byte	3
+		.word	$2000
+		.word	$3000
+	</verb></tscreen>
+
+	Since the variable is of type <tt/void/ you may not use it as is. 
+	However, taking the address of the variable results in a <tt/void*/
+	which may be passed to any function expecting a pointer.
+
+	See the <htmlurl url="geos.html" name="GEOS library"> for examples on
+	how to use this feature.
+	<p>
+
 </itemize>
 <p>