diff --git a/include/bx/inline/string.inl b/include/bx/inline/string.inl
index 4bec9dd..d4fab31 100644
--- a/include/bx/inline/string.inl
+++ b/include/bx/inline/string.inl
@@ -124,6 +124,7 @@ namespace bx
 		{
 			m_len = INT32_MAX == _len ? strLen(_ptr) : _len;
 			m_ptr = _ptr;
+			m_0terminated = INT32_MAX == _len;
 		}
 	}
 
@@ -149,6 +150,7 @@ namespace bx
 	{
 		m_ptr = "";
 		m_len = 0;
+		m_0terminated = true;
 	}
 
 	inline const char* StringView::getPtr() const
@@ -171,28 +173,31 @@ namespace bx
 		return m_len;
 	}
 
+	inline bool StringView::is0Terminated() const
+	{
+		return m_0terminated;
+	}
+
 	template<bx::AllocatorI** AllocatorT>
 	inline StringT<AllocatorT>::StringT()
 		: StringView()
+		, m_capacity(0)
 	{
+		clear();
 	}
 
 	template<bx::AllocatorI** AllocatorT>
 	inline StringT<AllocatorT>::StringT(const StringT<AllocatorT>& _rhs)
 		: StringView()
+		, m_capacity(0)
 	{
 		set(_rhs);
 	}
 
-	template<bx::AllocatorI** AllocatorT>
-	inline StringT<AllocatorT>& StringT<AllocatorT>::operator=(const StringT<AllocatorT>& _rhs)
-	{
-		set(_rhs);
-		return *this;
-	}
-
 	template<bx::AllocatorI** AllocatorT>
 	inline StringT<AllocatorT>::StringT(const StringView& _rhs)
+		: StringView()
+		, m_capacity(0)
 	{
 		set(_rhs);
 	}
@@ -203,6 +208,13 @@ namespace bx
 		clear();
 	}
 
+	template<bx::AllocatorI** AllocatorT>
+	inline StringT<AllocatorT>& StringT<AllocatorT>::operator=(const StringT<AllocatorT>& _rhs)
+	{
+		set(_rhs);
+		return *this;
+	}
+
 	template<bx::AllocatorI** AllocatorT>
 	inline void StringT<AllocatorT>::set(const StringView& _str)
 	{
@@ -215,13 +227,22 @@ namespace bx
 	{
 		if (0 != _str.getLength() )
 		{
-			int32_t old = m_len;
-			int32_t len = m_len + strLen(_str);
-			char* ptr = (char*)BX_REALLOC(*AllocatorT, 0 != m_len ? const_cast<char*>(m_ptr) : NULL, len+1);
+			const int32_t old = m_len;
+			const int32_t len = m_len + _str.getLength();
+
+			char* ptr = const_cast<char*>(m_ptr);
+
+			if (len+1 > m_capacity)
+			{
+				const int32_t capacity = alignUp(len+1, 256);
+				ptr = (char*)BX_REALLOC(*AllocatorT, 0 != m_capacity ? ptr : NULL, capacity);
+
+				*const_cast<char**>(&m_ptr) = ptr;
+				m_capacity = capacity;
+			}
+
 			m_len = len;
 			strCopy(ptr + old, len-old+1, _str);
-
-			*const_cast<char**>(&m_ptr) = ptr;
 		}
 	}
 
@@ -234,11 +255,14 @@ namespace bx
 	template<bx::AllocatorI** AllocatorT>
 	inline void StringT<AllocatorT>::clear()
 	{
-		if (0 != m_len)
+		m_0terminated = true;
+
+		if (0 != m_capacity)
 		{
 			BX_FREE(*AllocatorT, const_cast<char*>(m_ptr) );
 
 			StringView::clear();
+			m_capacity = 0;
 		}
 	}
 
diff --git a/include/bx/string.h b/include/bx/string.h
index 87910b6..5360e12 100644
--- a/include/bx/string.h
+++ b/include/bx/string.h
@@ -91,15 +91,19 @@ namespace bx
 		///
 		const char* getTerm() const;
 
-		///
+		/// Returns `true` if string is empty.
 		bool isEmpty() const;
 
-		///
+		/// Returns string length.
 		int32_t getLength() const;
 
+		/// Returns `true` if string is zero terminated.
+		bool is0Terminated() const;
+
 	protected:
 		const char* m_ptr;
 		int32_t     m_len;
+		bool        m_0terminated;
 	};
 
 	/// ASCII string
@@ -113,15 +117,15 @@ namespace bx
 		///
 		StringT(const StringT<AllocatorT>& _rhs);
 
-		///
-		StringT<AllocatorT>& operator=(const StringT<AllocatorT>& _rhs);
-
 		///
 		StringT(const StringView& _rhs);
 
 		///
 		~StringT();
 
+		///
+		StringT<AllocatorT>& operator=(const StringT<AllocatorT>& _rhs);
+
 		///
 		void set(const StringView& _str);
 
@@ -137,6 +141,9 @@ namespace bx
 		/// Returns zero-terminated C string pointer.
 		///
 		const char* getCPtr() const;
+
+	protected:
+		int32_t m_capacity;
 	};
 
 	/// Retruns true if character is part of space set.
diff --git a/src/string.cpp b/src/string.cpp
index c884948..fb5afed 100644
--- a/src/string.cpp
+++ b/src/string.cpp
@@ -813,6 +813,11 @@ namespace bx
 			return write(_writer, _str, _param.prec, _param, _err);
 		}
 
+		static int32_t write(WriterI* _writer, const StringView& _str, const Param& _param, Error* _err)
+		{
+			return write(_writer, _str.getPtr(), min(_param.prec, _str.getLength() ), _param, _err);
+		}
+
 		static int32_t write(WriterI* _writer, int32_t _i, const Param& _param, Error* _err)
 		{
 			char str[33];
@@ -939,12 +944,15 @@ namespace bx
 			}
 			else if ('%' == ch)
 			{
-				// %[flags][width][.precision][length sub-specifier]specifier
+				// %[Flags][Width][.Precision][Leegth]Type
 				read(&reader, ch, &err);
 
 				Param param;
 
-				// flags
+				// Reference(s):
+				//  - Flags field
+				//    https://en.wikipedia.org/wiki/Printf_format_string#Flags_field
+				//
 				while (err.isOk()
 				&& (   ' ' == ch
 				||     '-' == ch
@@ -971,7 +979,10 @@ namespace bx
 					param.fill = ' ';
 				}
 
-				// width
+				// Reference(s):
+				//  - Width field
+				//    https://en.wikipedia.org/wiki/Printf_format_string#Width_field
+				//
 				if ('*' == ch)
 				{
 					read(&reader, ch, &err);
@@ -994,7 +1005,9 @@ namespace bx
 					}
 				}
 
-				// .precision
+				// Reference(s):
+				//  - Precision field
+				//    https://en.wikipedia.org/wiki/Printf_format_string#Precision_field
 				if ('.' == ch)
 				{
 					read(&reader, ch, &err);
@@ -1016,7 +1029,9 @@ namespace bx
 					}
 				}
 
-				// length sub-specifier
+				// Reference(s):
+				//  - Length field
+				//    https://en.wikipedia.org/wiki/Printf_format_string#Length_field
 				while (err.isOk()
 				&& (   'h' == ch
 				||     'I' == ch
@@ -1031,8 +1046,8 @@ namespace bx
 						default: break;
 
 						case 'j': param.bits = sizeof(intmax_t )*8; break;
-						case 't': param.bits = sizeof(size_t   )*8; break;
-						case 'z': param.bits = sizeof(ptrdiff_t)*8; break;
+						case 't': param.bits = sizeof(ptrdiff_t)*8; break;
+						case 'z': param.bits = sizeof(size_t   )*8; break;
 
 						case 'h': case 'I': case 'l':
 							switch (ch)
@@ -1071,7 +1086,9 @@ namespace bx
 					break;
 				}
 
-				// specifier
+				// Reference(s):
+				//  - Type field
+				//    https://en.wikipedia.org/wiki/Printf_format_string#Type_field
 				switch (toLower(ch) )
 				{
 					case 'c':
@@ -1079,7 +1096,14 @@ namespace bx
 						break;
 
 					case 's':
-						size += write(_writer, va_arg(_argList, const char*), param, _err);
+						if (isUpper(ch) )
+						{
+							size += write(_writer, va_arg(_argList, const StringView), param, _err);
+						}
+						else
+						{
+							size += write(_writer, va_arg(_argList, const char*), param, _err);
+						}
 						break;
 
 					case 'o':
@@ -1131,6 +1155,10 @@ namespace bx
 						}
 						break;
 
+					case 'n':
+						*va_arg(_argList, int32_t*) = size;
+						break;
+
 					default:
 						size += write(_writer, ch, _err);
 						break;
diff --git a/tests/string_test.cpp b/tests/string_test.cpp
index ca820c4..5524d91 100644
--- a/tests/string_test.cpp
+++ b/tests/string_test.cpp
@@ -555,3 +555,29 @@ TEST_CASE("suffix", "")
 	REQUIRE(0 == bx::strCmp(bx::strTrimSuffix("abvgd-1389.0", "389.0"), "abvgd-1") );
 	REQUIRE(0 == bx::strCmp(bx::strTrimSuffix("abvgd-1389.0", "xyz"), "abvgd-1389.0") );
 }
+
+TEST_CASE("0terminated", "")
+{
+	const bx::StringView t0("1389");
+	REQUIRE(t0.is0Terminated() );
+	const bx::StringView t1(strTrimPrefix(t0, "13") );
+	REQUIRE(!t1.is0Terminated() );
+	const bx::StringView t2(strTrimSuffix(t0, "89") );
+	REQUIRE(!t2.is0Terminated() );
+
+	bx::DefaultAllocator crt;
+	g_allocator = &crt;
+
+	typedef bx::StringT<&g_allocator> String;
+
+	String st;
+	REQUIRE(st.is0Terminated() );
+
+	st = strTrimPrefix(t0, "13");
+	REQUIRE(2 == st.getLength() );
+	REQUIRE(st.is0Terminated() );
+
+	st = strTrimSuffix(t0, "89");
+	REQUIRE(2 == st.getLength() );
+	REQUIRE(st.is0Terminated() );
+}
diff --git a/tests/vsnprintf_test.cpp b/tests/vsnprintf_test.cpp
index e65b70c..2cf1416 100644
--- a/tests/vsnprintf_test.cpp
+++ b/tests/vsnprintf_test.cpp
@@ -184,6 +184,22 @@ TEST_CASE("vsnprintf t")
 	size_t size = -1;
 
 	REQUIRE(test("-1", "%td", size) );
+
+	REQUIRE(test("3221225472", "%td", size_t(3221225472) ) );
+}
+
+TEST_CASE("vsnprintf n")
+{
+	char temp[64];
+
+	int32_t p0, p1, p2;
+	bx::snprintf(temp, sizeof(temp), "%n", &p0);
+	REQUIRE(0 == p0);
+
+	bx::snprintf(temp, sizeof(temp), "01%n23%n45%n", &p0, &p1, &p2);
+	REQUIRE(2 == p0);
+	REQUIRE(4 == p1);
+	REQUIRE(6 == p2);
 }
 
 TEST_CASE("vsnprintf g")
@@ -215,6 +231,11 @@ TEST_CASE("vsnprintf")
 		, hello.getLength(), hello.getPtr()
 		, world.getLength(), world.getPtr()
 		) );
+
+	REQUIRE(test("hello, world!", "%S, %S!"
+		, hello
+		, world
+		) );
 }
 
 TEST_CASE("vsnprintf write")