Adding PORTING notes.

diff --git a/PORTING b/PORTING
new file mode 100644 (file)
index 0000000..98d22f4
--- /dev/null
+++ b/PORTING
@@ -0,0 +1,4 @@
+To see declarations made by the gcc compiler, can be useful for determining
+platform specific declartions:
+
+    gcc -dM -E - < /dev/null