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_mbsnbcpy, _mbsnbcpy_l

Copies n bytes of a string to a destination string. More secure versions of these functions are available—see _mbsnbcpy_s, _mbsnbcpy_s_l.

Important

This API cannot be used in applications that execute in the Windows Runtime. For more information, see CRT functions not supported in Universal Windows Platform apps.

Syntax

unsigned char * _mbsnbcpy(
   unsigned char * strDest,
   const unsigned char * strSource,
   size_t count
);
unsigned char * _mbsnbcpy_l(
   unsigned char * strDest,
   const unsigned char * strSource,
   size_t count,
   _locale_t locale
);
template <size_t size>
unsigned char * _mbsnbcpy(
   unsigned char (&strDest)[size],
   const unsigned char * strSource,
   size_t count
); // C++ only
template <size_t size>
unsigned char * _mbsnbcpy_l(
   unsigned char (&strDest)[size],
   const unsigned char * strSource,
   size_t count,
   _locale_t locale
); // C++ only

Parameters

strDest
Destination for the character string to be copied.

strSource
Character string to be copied.

count
Number of bytes to be copied.

locale
Locale to use.

Return value

_mbsnbcpy returns a pointer to the destination character string. No return value is reserved to indicate an error.

Remarks

The _mbsnbcpy function copies count bytes from strSource to strDest. If count exceeds the size of strDest or the source and destination strings overlap, the behavior of _mbsnbcpy is undefined.

If strSource or strDest is a null pointer, this function invokes the invalid parameter handler as described in Parameter validation. If execution is allowed to continue, the function returns NULL and sets errno to EINVAL.

The output value is affected by the setting of the LC_CTYPE category setting of the locale. For more information, see setlocale. The versions of these functions are identical, except that the ones that don't have the _l suffix use the current locale and the versions that do have the _l suffix instead use the locale parameter that's passed in. For more information, see Locale.

Important

These functions might be vulnerable to buffer overrun threats. Buffer overruns can be used to execute arbitrary attacker code, which can cause an unwarranted elevation of privilege and compromise the system. For more information, see Avoiding buffer overruns.

In C++, these functions have template overloads that invoke the newer, more secure counterparts of these functions. For more information, see Secure template overloads.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Generic-text routine mappings

Tchar.h routine _UNICODE and _MBCS not defined _MBCS defined _UNICODE defined
_tcsncpy strncpy _mbsnbcpy wcsncpy
_tcsncpy_l _strncpy_l _mbsnbcp_l _wcsncpy_l

Requirements

Routine Required header
_mbsnbcpy <mbstring.h>
_mbsnbcpy_l <mbstring.h>

For more compatibility information, see Compatibility.

See also

String manipulation
_mbsnbcat, _mbsnbcat_l
_mbsnbcmp, _mbsnbcmp_l
_strncnt, _wcsncnt, _mbsnbcnt, _mbsnbcnt_l, _mbsnccnt, _mbsnccnt_l
_mbsnbset, _mbsnbset_l
strncpy, _strncpy_l, wcsncpy, _wcsncpy_l, _mbsncpy, _mbsncpy_l