site: Update docs, add some details about Xcode

src/site/markdown/crosscomp.md

@@ -137,3 +137,7 @@ the JNI code as follows:
 
 Right now, crossclang only supports C and C++. However, adding support other languages should
 be relatively straightforward.
+
+## See also
+
+[Developing with Xcode](xcode.html).

src/site/markdown/development.md

@@ -9,6 +9,8 @@ Here are some instructions to get started.
 
    * [Developing with Eclipse](eclipse.html) 
 
+   * [Developing with Xcode](xcode.html)
+
    * [Custom architectures: Building and running](customarch.html)
 
    * [Cross-compiling junixsocket](crosscomp.html)

src/site/markdown/xcode.md

@@ -0,0 +1,35 @@
+# Developing with Xcode
+
+The recommended editor for working with the native C code is Xcode. Even for non-Apple targets.
+
+This works thanks to crossclang, also see [Cross-compiling junixsocket](crosscomp.html).
+
+## Setup
+
+In order to develop with Xcode, using crossclang, you need to install a custom Xcode SDK.
+
+Run the following script from the Terminal, which creates a symbolic link under
+`~/Library/Developer/Toolchains` to the `crossclang.sdk`, which essentially tells Xcode to use
+our "crossclang" clang wrapper script instead of its built-in version, among other things.
+
+    ./junixsocket-native/crossclang/Xcode-Support/install
+
+You then need to:
+
+1. Restart Xcode
+2. Set the Toolchain to "crossclang" (via Xcode -> Toolchains..., or via a button in the launch window)
+3. Open junixsocket-native.xcodeproj
+4. Run "Clean Build Folder"
+5. Run "Build"
+
+Note that you need to switch back to the default Xcode Toolchain when you develop other projects. 
+
+## Building from the command-line
+
+AFter installing the "crossclang" Toolchain, you can also build from the command-line.
+In this case, you don't have to switch the Toolchain via Xcode:
+
+    xcodebuild -project junixsocket-native/junixsocket-native.xcodeproj -configuration Release \
+        -target "All Architectures" -toolchain crossclang USE_HEADERMAP=NO \
+        CURRENT_ARCH=undefined_arch arch=undefined_arch ARCHS=arm64 CODE_SIGNING_ALLOWED=NO \
+        clean build