[PATCH] introduction: add note on bitfield portability

["Michael S. Tsirkin" <mst@redhat.com>]

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 introduction.tex | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/introduction.tex b/introduction.tex
index d0b770e..18ad76e 100644
--- a/introduction.tex
+++ b/introduction.tex
@@ -175,5 +175,12 @@ packed by C compilers on little-endian architectures but not the
 way bitfields are packed by C compilers on big-endian
 architectures.
 
+Assuming that CPU_TO_BE16 converts a 16-bit integer from a native
+CPU to the big-endian byte order, the following is the equivalent
+portable C code to generate a value in this format:
+\begin{lstlisting}
+CPU_TO_BE16(B << 15 | A)
+\end{lstlisting}
+
 \newpage
 
-- 
MST