[MLton-user] FFI question: converting C strings to ML

[John Reppy]

The following situation is quite common, but I haven't been able to find
a simple way to handle it in MLton's FFI.  Say that we have a C function

	const char *getString (int name);

that returns either a pointer to a C-style nul-terminated string or 0  
when there
is an error.  I'd like to map the result to an ML string or an  
exception.

Right now, my code is

	val charPtr = getString(name)
	val mlString = if (MLton.Pointer.null = charPtr)
	      then let
		val len = strlen charPtr
		val buf = CharArray.array(len, #" ")
		val _ = strncpy (buf, charPtr, len)
		in
		  CharArray.vector buf
		end
	      else raise Fail "null pointer"

where getString, strlen, and strncpy are imported C functions.  Is  
there a better
way to do this conversion?

	- John