strncpy, wcsncpy, _mbsncpy
Copy characters of one string to another.
char*strncpy(char*strDest,constchar*strSource,size_tcount**);**
wchar_t*wcsncpy(wchar_t*strDest,constwchar_t*strSource,size_tcount**);**
unsignedchar*_mbsncpy(unsignedchar*strDest,constunsignedchar*strSource,size_tcount**);**
| Routine | Required Header | Compatibility |
| strncpy | <string.h> | ANSI, Win 95, Win NT |
| wcsncpy | <string.h> or <wchar.h> | ANSI, Win 95, Win NT |
| _mbsncpy | <mbstring.h> | Win 95, Win NT |
For additional compatibility information, see Compatibility in the Introduction.
Libraries
| LIBC.LIB | Single thread static library, retail version |
| LIBCMT.LIB | Multithread static library, retail version |
| MSVCRT.LIB | Import library for MSVCRT.DLL, retail version |
Return Value
Each of these functions returns strDest. No return value is reserved to indicate an error.
Parameters
strDest
Destination string
strSource
Source string
count
Number of characters to be copied
Remarks
The strncpy function copies the initial count characters of strSource to strDest and returns strDest. If count is less than or equal to the length of strSource, a null character is not appended automatically to the copied string. If count is greater than the length of strSource, the destination string is padded with null characters up to length count. The behavior of strncpy is undefined if the source and destination strings overlap.
wcsncpy and _mbsncpy are wide-character and multibyte-character versions of strncpy. The arguments and return value of wcsncpy and _mbsncpy vary accordingly. These three functions behave identically otherwise.
Generic-Text Routine Mappings
| TCHAR.H Routine | _UNICODE & _MBCS Not Defined | _MBCS Defined | _UNICODE Defined |
| _tcsncpy | strncpy | _mbsnbcpy | wcsncpy |
Example
/* STRNCPY.C */
#include <string.h>
#include <stdio.h>
void main( void )
{
char string[100] = "Cats are nice usually";
printf ( "Before: %s\n", string );
strncpy( string, "Dogs", 4 );
strncpy( string + 9, "mean", 4 );
printf ( "After: %s\n", string );
}
Output
Before: Cats are nice usually
After: Dogs are mean usually
See Also _mbsnbcpy, strcat, strcmp, strcpy, strncat, strncmp, _strnicmp, strrchr, _strset, strspn