Merge pull request #4381 from amyw-msft/patch-18

Update %Z specifier with known issue

Author: Jak-MS

docs/c-runtime-library/format-specification-syntax-printf-and-wprintf-functions.md

@@ -65,7 +65,7 @@ Integer types such as `short`, `int`, `long`, `long long`, and their `unsigned`
 | **`p`** | Pointer type | Display the argument as an address in hexadecimal digits. |
 | **`s`** | String | When used with `printf` functions, specifies a single-byte or multi-byte character string; when used with `wprintf` functions, specifies a wide-character string. Characters are displayed up to the first null character or until the *precision* value is reached. |
 | **`S`** | String | When used with `printf` functions, specifies a wide-character string; when used with `wprintf` functions, specifies a single-byte or multi-byte character string. Characters are displayed up to the first null character or until the *precision* value is reached. |
-| **`Z`** | `ANSI_STRING` or `UNICODE_STRING` structure | When the address of an [`ANSI_STRING`](/windows/win32/api/ntdef/ns-ntdef-string) or [`UNICODE_STRING`](/windows/win32/api/ntdef/ns-ntdef-_unicode_string) structure is passed as the argument, display the string contained in the buffer pointed to by the `Buffer` field of the structure. Use a *size* modifier prefix of **`w`** to specify a `UNICODE_STRING` argument—for example, `%wZ`. The `Length` field of the structure must be set to the length, in bytes, of the string. The `MaximumLength` field of the structure must be set to the length, in bytes, of the buffer.<br /><br />Typically, the **`Z`** type character is used only in driver debugging functions that use a conversion specification, such as `dbgPrint` and `kdPrint`. |
+| **`Z`** | `ANSI_STRING` or `UNICODE_STRING` structure | **VS 2013 and earlier** <br /> When the address of an [`ANSI_STRING`](/windows/win32/api/ntdef/ns-ntdef-string) or [`UNICODE_STRING`](/windows/win32/api/ntdef/ns-ntdef-_unicode_string) structure is passed as the argument, display the string contained in the buffer pointed to by the `Buffer` field of the structure. Use a *size* modifier prefix of **`w`** to specify a `UNICODE_STRING` argument—for example, `%wZ`. The `Length` field of the structure must be set to the length, in bytes, of the string. The `MaximumLength` field of the structure must be set to the length, in bytes, of the buffer.<br /><br /> **Universal C Runtime (UCRT)**<br />There is a known issue in the UCRT that is currently maintained for compatibility. Like the **`S`** specifier, the **`Z`** specifier without a size modifier prefix refers to a `UNICODE_STRING` when using a narrow printing function (like `printf`) and an `ANSI_STRING` when using a wide printing function (like `wprintf`).<br /> Instead of **`Z`**, use **`hZ`** to specify an `ANSI_STRING`. **`wZ`** (or **`lZ`**) can still be used to specify a `UNICODE_STRING`. <br /><br />Typically, the **`Z`** type character is used only in driver debugging functions that use a conversion specification, such as `dbgPrint` and `kdPrint`. |
 
 In Visual Studio 2015 and later versions, if the argument that corresponds to a floating-point conversion specifier (**`a`**, **`A`**, **`e`**, **`E`**, **`f`**, **`F`**, **`g`**, **`G`**) is infinite, indefinite, or NaN, the formatted output conforms to the C99 standard. This table lists the formatted output: