Update README.md

1 files changed, 22 insertions, 11 deletions

diff --git a/README.md b/README.md
index 6ef43c2..5e12ea8 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 About
 -----
 This is a library for calling C function and manipulating C types from lua. It
-is designed to be interface compatible with the FFI library in luajit (see
+is designed to be interface compatible with the FFI library in LuaJIT (see
 http://luajit.org/ext_ffi.html). It can parse C function declarations and
 struct definitions that have been directly copied out of C header files and
 into lua source as a string.
@@ -16,7 +16,7 @@ Platforms
 ---------
 Currently supported:
 - Linux x86/x64
-- OSX x86/x64
+- OS X x86/x64
 
 Runs with both Lua 5.1 and Lua 5.2.
 
@@ -24,13 +24,24 @@ Build
 -----
 - Run `luarocks make`
 
+Documentation
+-------------
+This library is designed to be source compatible with LuaJIT's FFI extension. The documentation at http://luajit.org/ext_ffi.html describes the API and semantics.
+
+Pointer Comparison
+------------
+Use `ffi.NULL` instead of `nil` when checking for `NULL` pointers.
+```lua
+  ffi.new('void *', 0) == ffi.NULL -- true
+```
+
 Known Issues
 ------------
-- Comparing a ctype pointer to nil doesn't work the same as luajit. This is
-  unfixable with the current metamethod semantics. Instead use ffi.NULL
+- Comparing a ctype pointer to `nil` doesn't work the same as in LuaJIT (see above).
+  This is unfixable with the current metamethod semantics.
 - Constant expressions can't handle non integer intermediate values (eg
   offsetof won't work because it manipulates pointers)
-- Not all metamethods work with lua 5.1 (eg char* + number). This is due to
+- Not all metamethods work with Lua 5.1 (eg char* + number). This is due to
   the way metamethods are looked up with mixed types in Lua 5.1. If you need
 this upgrade to Lua 5.2 or use boxed numbers (uint64_t and uintptr_t).
 - All bitfields are treated as unsigned (does anyone even use signed
@@ -53,15 +64,15 @@ Boxed cdata types are pushed into lua as a userdata containing the struct
 cdata structure (which contains the struct ctype of the data as its header)
 followed by the boxed data.
 
-The functions in ffi.c provide the cdata and ctype metatables and ffi.*
+The functions in `ffi.C` provide the `cdata` and `ctype` metatables and ffi.*
 functions which manipulate these two types.
 
 C functions (and function pointers) are pushed into lua as a lua c function
 with the function pointer cdata as the first upvalue. The actual code is JITed
 using dynasm (see call_x86.dasc). The JITed code does the following in order:
-1. Calls the needed unpack functions in ffi.c placing each argument on the HW stack
-2. Updates errno
-3. Performs the c call
-4. Retrieves errno
-5. Pushes the result back into lua from the HW register or stack
 
+1. Calls the needed unpack functions in `ffi.C` placing each argument on the HW stack
+2. Updates `errno`
+3. Performs the C call
+4. Retrieves `errno`
+5. Pushes the result back into lua from the HW register or stack