Wrapped the init example in a main() for maximum clarity.

doc/init-main.md

@@ -15,6 +15,8 @@ Furthermore, on some systems, this thread must also be the thread that `main()`
 Here is an example of correct use of `uiInit()` in C:
 
 ```c
+int main(void)
+{
 	uiInitError err;
 
 	memset(&err, 0, sizeof (uiInitError));
@@ -23,6 +25,8 @@ if (!uiInit(NULL, &err)) {
 		fprintf(stderr, "error initializing libui: %s\n", err.Message);
 		return 1;
 	}
+	// ...
+}
 ```
 
 Note that if `uiInit()` fails, you **cannot** use libui's message box functions to report the error.