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memcpy, wmemcpy

Copies bytes between buffers. More secure versions of these functions are available; see memcpy_s, wmemcpy_s.

void *memcpy(
   void *dest,
   const void *src,
   size_t count 
);
wchar_t *wmemcpy(
   wchar_t *dest,
   const wchar_t *src,
   size_t count
);

Parameters

  • dest
    New buffer.

  • src
    Buffer to copy from.

  • count
    Number of characters to copy.

Return Value

The value of dest.

Remarks

memcpy copies count bytes from src to dest; wmemcpy copies count wide characters (two bytes). If the source and destination overlap, the behavior of memcpy is undefined. Use memmove to handle overlapping regions.

Security Note Make sure that the destination buffer is the same size or larger than the source buffer. For more information, see Avoiding Buffer Overruns.

The memcpy and wmemcpy functions will only be deprecated if the constant _CRT_SECURE_DEPRECATE_MEMORY is defined prior to the inclusion statement in order for the functions to be deprecated, such as in the example below:

#define _CRT_SECURE_DEPRECATE_MEMORY
#include <memory.h>

or

#define _CRT_SECURE_DEPRECATE_MEMORY
#include <wchar.h>

Requirements

Routine

Required header

memcpy

<memory.h> or <string.h>

wmemcpy

<wchar.h>

For additional compatibility information, see Compatibility in the Introduction.

Example

See memmove for a sample of how to use memcpy.

See Also

Reference

Buffer Manipulation

_memccpy

memchr, wmemchr

memcmp, wmemcmp

memmove, wmemmove

memset, wmemset

strcpy_s, wcscpy_s, _mbscpy_s

strncpy_s, _strncpy_s_l, wcsncpy_s, _wcsncpy_s_l, _mbsncpy_s, _mbsncpy_s_l