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strstr, wcsstr, _mbsstr

Visual Studio .NET 2003

Returns a pointer to the first occurrence of a search string in a string.

char *strstr(
   const char *string,
   const char *strSearch 
);
wchar_t *wcsstr(
   const wchar_t *string,
   const wchar_t *strSearch 
);
unsigned char *_mbsstr(
   const unsigned char *string,
   const unsigned char *strSearch 
);

Parameters

string: Null-terminated string to search.
strSearch: Null-terminated string to search for.

Return Value

Returns a pointer to the first occurrence of strSearch in string, or NULL if strSearch does not appear in string. If strSearch points to a string of zero length, the function returns string.

Remarks

The strstr function returns a pointer to the first occurrence of strSearch in string. The search does not include terminating null characters. wcsstr and _mbsstr are wide-character and multibyte-character versions of strstr. The arguments and return value of wcsstr are wide-character strings; those of _mbsstr are multibyte-character strings. These three functions behave identically otherwise.

Security Note These functions incur a potential threat brought about by a buffer overrun problem. Buffer overrun problems are a frequent method of system attack, resulting in an unwarranted elevation of privilege. For more information, see Avoiding Buffer Overruns.

Generic-Text Routine Mappings

TCHAR.H routine	_UNICODE & _MBCS not defined	_MBCS defined	_UNICODE defined
_tcsstr	strstr	_mbsstr	wcsstr

Requirements

Routine	Required header	Compatibility
strstr	<string.h>	ANSI, Win 98, Win Me, Win NT, Win 2000, Win XP
wcsstr	<string.h> or <wchar.h>	ANSI, Win 98, Win Me, Win NT, Win 2000, Win XP
_mbsstr	<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_strstr.c

#include <string.h>
#include <stdio.h>

char str[] =    "lazy";
char string[] = "The quick brown dog jumps over the lazy fox";
char fmt1[] =   "         1         2         3         4         5";
char fmt2[] =   "12345678901234567890123456789012345678901234567890";

int main( void )
{
   char *pdest;
   int  result;
   printf( "String to be searched:\n   %s\n", string );
   printf( "   %s\n   %s\n\n", fmt1, fmt2 );
   pdest = strstr( string, str );
   result = (int)(pdest - string + 1);
   if ( pdest != NULL )
      printf( "%s found at position %d\n", str, result );
   else
      printf( "%s not found\n", str );
}

Output

String to be searched:
   The quick brown dog jumps over the lazy fox
            1         2         3         4         5
   12345678901234567890123456789012345678901234567890

lazy found at position 36