printk.

diff --git a/01.hello/01.hello.xml b/01.hello/01.hello.xml
index 954422f..5f424e6 100644 (file)
--- a/01.hello/01.hello.xml
+++ b/01.hello/01.hello.xml
@@ -50,6 +50,16 @@ kernel to remove them when they are not needed, reducing memory consumption.
 </para>
 </foil>
 
+<foil>
+<title>printk</title>
+<para>
+<emphasis>printk</emphasis> is very similar to printf. The messages are usually
+preceded by a string in the form &lt;n&gt;, where <emphasis>n</emphasis> is a
+priority. There are macros, like <emphasis>KERN\_ALERT</emphasis> and
+<emphasis>KERN\_DEBUG</emphasis> to use for that.
+</para>
+</foil>
+
 <foil>
 <title>Building</title>
 <para>