_strdup, _wcsdup, _mbsdup
Duplicate strings.
char *_strdup( const char *strSource ); wchar_t *_wcsdup( const wchar_t *strSource ); unsigned char *_mbsdup( const unsigned char *strSource );
Parameters
- strSource
- Null-terminated source string.
Return Value
Each of these functions returns a pointer to the storage location for the copied string or NULL if storage cannot be allocated.
Remarks
The _strdup function calls malloc to allocate storage space for a copy of strSource and then copies strSource to the allocated space.
_wcsdup and _mbsdup are wide-character and multibyte-character versions of _strdup. The arguments and return value of _wcsdup are wide-character strings; those of _mbsdup are multibyte-character strings. These three functions behave identically otherwise.
Generic-Text Routine Mappings
| TCHAR.H routine | _UNICODE & _MBCS not defined | _MBCS defined | _UNICODE defined |
|---|---|---|---|
| _tcsdup | _strdup | _mbsdup | _wcsdup |
Because _strdup calls malloc to allocate storage space for the copy of strSource, it is good practice always to release this memory by calling the free routine on the pointer returned by the call to _strdup.
Requirements
| Routine | Required header | Compatibility |
|---|---|---|
| _strdup | <string.h> | Win 98, Win Me, Win NT, Win 2000, Win XP |
| _wcsdup | <string.h> or <wchar.h> | Win 98, Win Me, Win NT, Win 2000, Win XP |
| _mbsdup | <mbstring.h> | Win 98, Win Me, Win NT, Win 2000, Win XP |
For additional compatibility information, see Compatibility in the Introduction.
Libraries
All versions of the C run-time libraries.
Example
// crt_strdup.c
#include <string.h>
#include <stdio.h>
int main( void )
{
char buffer[] = "This is the buffer text";
char *newstring;
printf( "Original: %s\n", buffer );
newstring = _strdup( buffer );
printf( "Copy: %s\n", newstring );
free( newstring );
}
Output
Original: This is the buffer text Copy: This is the buffer text
See Also
String Manipulation Routines | memset | strcat | strcmp | strncat | strncmp | strncpy | _strnicmp | strrchr | strspn | Run-Time Routines and .NET Framework Equivalents
