_mbsnbcpy_s, _mbsnbcpy_s_l
Copies n bytes of a string to a destination string. These are versions of _mbsnbcpy, _mbsnbcpy_l with security enhancements as described in Security Enhancements in the CRT.
errno_t _mbsnbcpy_s( unsigned char * strDest, size_t sizeInBytes, const unsigned char * strSource, size_t count ); errno_t _mbsnbcpy_s_l( unsigned char * strDest, size_t sizeInBytes, const unsigned char * strSource, size_t count, _locale_t locale ); template <size_t size> errno_t _mbsnbcpy_s( unsigned char (&strDest)[size], const unsigned char * strSource, size_t count ); // C++ only template <size_t size> errno_t _mbsnbcpy_s_l( unsigned char (&strDest)[size], const unsigned char * strSource, size_t count, _locale_t locale ); // C++ only
Parameters
- strDest
-
Destination for character string to be copied.
- sizeInBytes
-
Destination buffer size.
- strSource
-
Character string to be copied.
- count
-
Number of bytes to be copied.
- locale
-
Locale to use.
The _mbsnbcpy_s function copies count bytes from strSource to strDest. If count exceeds the size of strDest, either of the input strings is a null pointer, or sizeInBytes or count is 0, the function invokes the invalid parameter handler as described in Parameter Validation . If execution is allowed to continue, the function returns EINVAL. If the source and destination strings overlap, the behavior of _mbstrncpy is undefined.
The output value is affected by the setting of the LC_CTYPE category setting of the locale; see setlocale for more information. The versions of these functions without the _l suffix use the current locale for this locale-dependent behavior; the versions with the _l suffix are identical except that they use the locale parameter passed in instead.
 Note |
|---|
| Unlike the non-secure version of this function, _mbsnbcpy_s does not do any null padding and always null terminates the string. |
In C++, using these functions is simplified by template overloads; the overloads can infer buffer length automatically (eliminating the need to specify a size argument) and they can automatically replace older, non-secure functions with their newer, secure counterparts. For more information, see Secure Template Overloads.
The debug versions of these functions first fill the buffer with 0xFD.
| Tchar.h routine | _UNICODE and _MBCS not defined | _MBCS defined | _UNICODE defined |
|---|---|---|---|
| _tcsncpy_s | _strncpy_s | _mbsnbcpy_s | _wcsncpy_s |
| _tcsncpy_s_l | _strncpy_s_l | _mbsnbcpy_s_l | _wcsncpy_s_l |
| Routine | Required header | Compatibility |
|---|---|---|
| _mbsnbcpy_s | <mbstring.h> | Windows 95, Windows 98, Windows 98 Second Edition, Windows Millennium Edition, Windows NT 4.0, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 |
| _mbsnbcpy_s_l | <mbstring.h> | Windows 95, Windows 98, Windows 98 Second Edition, Windows Millennium Edition, Windows NT 4.0, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 |
For more compatibility information, see Compatibility in the Introduction.
Not applicable. To call the standard C function, use PInvoke. For more information, see Platform Invoke Examples.
