[gardening] Fix typo: "nul-terminated" → "null-terminated"

Author: peterfriese

include/swift/AST/Identifier.h

@@ -48,7 +48,7 @@ enum class DeclRefKind {
 };
 
 /// Identifier - This is an instance of a uniqued identifier created by
-/// ASTContext.  It just wraps a nul-terminated "const char*".
+/// ASTContext.  It just wraps a null-terminated "const char*".
 class Identifier {
   friend class ASTContext;
   const char *Pointer;

include/swift/Parse/Lexer.h

@@ -48,7 +48,7 @@ class Lexer {
 
   /// Pointer to one past the end character of the buffer, even in a lexer
   /// that scans a subrange of the buffer.  Because the buffer is always
-  /// NUL-terminated, this points to the NUL terminator.
+  /// NULL-terminated, this points to the NUL terminator.
   const char *BufferEnd;
 
   /// Pointer to the artificial EOF that is located before BufferEnd.  Useful

stdlib/public/SDK/Foundation/NSStringAPI.swift

@@ -594,7 +594,7 @@ extension String {
   /// `encoding`, without any allocations.  Does not NULL-terminate.
   ///
   /// - Parameter buffer: A buffer into which to store the bytes from
-  ///   the receiver. The returned bytes are not NUL-terminated.
+  ///   the receiver. The returned bytes are not NULL-terminated.
   ///
   /// - Parameter maxBufferCount: The maximum number of bytes to write
   ///   to buffer.

stdlib/public/core/LifetimeManager.swift

@@ -31,7 +31,7 @@ public func withExtendedLifetime<T, Result>(
 extension String {
 
   /// Invoke `f` on the contents of this string, represented as
-  /// a nul-terminated array of char, ensuring that the array's
+  /// a null-terminated array of char, ensuring that the array's
   /// lifetime extends through the execution of `f`.
   public func withCString<Result>(
     @noescape f: UnsafePointer<Int8> throws -> Result

stdlib/public/core/StringUTF8.swift

@@ -247,7 +247,7 @@ extension String {
     return _core.elementWidth == 1 ? _core.startASCII : nil
   }
 
-  /// A contiguously-stored nul-terminated UTF-8 representation of
+  /// A contiguously-stored null-terminated UTF-8 representation of
   /// `self`.
   ///
   /// To access the underlying memory, invoke

stdlib/public/runtime/Reflection.mm

@@ -94,7 +94,7 @@ explicit String(const char *ptr)
     : String(ptr, strlen(ptr))
   {}
 
-  /// Create a Swift String from two concatenated nul-terminated strings.
+  /// Create a Swift String from two concatenated null-terminated strings.
   explicit String(const char *ptr1, const char *ptr2) {
     size_t len1 = strlen(ptr1);
     size_t len2 = strlen(ptr2);