From eef467984d8992df1437a08e481dd87e2ba842fc Mon Sep 17 00:00:00 2001
From: Gabor Hojtsy <goba@php.net>
Date: Sun, 11 Nov 2001 12:29:50 +0000
Subject: [PATCH] Adding that nice version_compare function, with examples

git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@61976 c90b9560-bf6c-de11-be94-00142212c4b1
---
 functions/info.xml | 67 ++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 65 insertions(+), 2 deletions(-)

diff --git a/functions/info.xml b/functions/info.xml
index 3c2fce4338..cebe2e6d9f 100644
--- a/functions/info.xml
+++ b/functions/info.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.71 $ -->
+<!-- $Revision: 1.72 $ -->
  <reference id="ref.info">
   <title>PHP options &amp; information</title>
   <titleabbrev>PHP options/info</titleabbrev>
@@ -1483,7 +1483,8 @@ echo "Current PHP version: ".phpversion();
      </example>
     </para>
     <para>
-     See also <function>phpinfo</function>,
+     See also <function>version_compare</function>,
+     <function>phpinfo</function>,
      <function>phpcredits</function>,
      <function>php_logo_guid</function>,
      <function>zend_version</function>.
@@ -1723,6 +1724,68 @@ putenv ("UNIQID=$uniqid");
    </refsect1>
   </refentry>
 
+  <refentry id="function.version-compare">
+   <refnamediv>
+    <refname>version_compare</refname>
+    <refpurpose>Compares two "PHP-standardized" version number strings</refpurpose>
+   </refnamediv>
+   <refsect1>
+    <title>Description</title>
+    <funcsynopsis>
+     <funcprototype>
+      <funcdef>int <function>version_compare</function></funcdef>
+      <paramdef>string <parameter>version1</parameter></paramdef>
+      <paramdef>string <parameter>version2</parameter></paramdef>
+      <paramdef>string 
+       <parameter>
+        <optional>operator</optional>
+       </parameter>
+      </paramdef>
+     </funcprototype>
+    </funcsynopsis>
+    <para>
+     <function>version_compare</function> compares
+     two "PHP-standardized" version number strings. This
+     is useful if you would like to write programs working
+     only on some versions of PHP.
+    </para>
+    <para>
+     <function>version_compare</function> returns -1 if
+     the first version is lower than the second, 0 if they
+     are equal, and +1 if the second is lower.
+    </para>
+    <para>
+     If you specify the third optional
+     <parameter>operator</parameter> argument, you
+     can test for a particular relationship. The possible
+     operators are: <literal>&lt;</literal>,
+     <literal>lt</literal>, <literal>&lt;=</literal>,
+     <literal>le</literal>, <literal>&gt;</literal>,
+     <literal>gt</literal>, <literal>&gt;=</literal>,
+     <literal>ge</literal>, <literal>==</literal>,
+     <literal>=</literal>, <literal>eq</literal>,
+     <literal>!=</literal>, <literal>&lt;&gt;</literal>,
+     <literal>ne</literal> respectively. Using
+     this argument, the function will return 1 if
+     the realtionship is the one specified by the
+     operator, 0 otherwise.
+    </para>
+    <para>
+     <example>
+      <title><function>version_compare</function> example</title>
+      <programlisting role="php">
+// prints -1
+echo version_compare("4.0.4", "4.0.6");
+
+// the all print 1
+echo version_compare("4.0.4", "4.0.6", "&lt;");
+echo version_compare("4.0.6", "4.0.6", "eq");
+      </programlisting>
+     </example>
+    </para>
+   </refsect1>
+  </refentry>
+
   <refentry id="function.zend-logo-guid">
    <refnamediv>
     <refname>zend_logo_guid</refname>