_scprintf, _scprintf_l, _scwprintf, _scwprintf_l

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06/05/2017

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Returns the number of characters in the formatted string.

Syntax

int _scprintf(  
   const char *format [,  
   argument] ...   
);  
int _scprintf_l(  
   const char *format,  
   locale_t locale [,  
   argument] ...   
);  
int _scwprintf(  
   const wchar_t *format [,  
   argument] ...   
);  
int _scwprintf_l(  
   const wchar_t *format,  
   locale_t locale [,  
   argument] ...   
);

Parameters

format
Format-control string.

argument
Optional arguments.

locale
The locale to use.

For more information, see Format Specifications.

Return Value

Returns the number of characters that would be generated if the string were to be printed or sent to a file or buffer using the specified formatting codes. The value returned does not include the terminating null character. _scwprintf performs the same function for wide characters.

If format is a NULL pointer, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, these functions return -1 and set errno to EINVAL.

For information about these and other error codes, see _doserrno, errno, _sys_errlist, and _sys_nerr.

Remarks

Each argument (if any) is converted according to the corresponding format specification in format. The format consists of ordinary characters and has the same form and function as the format argument for printf.

The versions of these functions with the _l suffix are identical except that they use the locale parameter passed in instead of the current thread locale.

Important

Ensure that format is not a user-defined string.

Generic-Text Routine Mappings

Tchar.h routine	_UNICODE and _MBCS not defined	_MBCS defined	_UNICODE defined
`_sctprintf`	`_scprintf`	`_scprintf`	`_scwprintf`
`_sctprintf_l`	`_scprintf_l`	`_scprintf_l`	`_scwprintf_l`

Requirements

Routine	Required header
`_scprintf`, `_scprintf_l`	<stdio.h>
`_scwprintf`, `_scwprintf_l`	<stdio.h> or <wchar.h>

For more compatibility information, see Compatibility in the Introduction.

Example

// crt__scprintf.c  
  
#define _USE_MATH_DEFINES  
  
#include <stdio.h>  
#include <math.h>  
#include <malloc.h>  
  
int main( void )  
{  
   int count;  
   int size;  
   char *s = NULL;  
  
   count = _scprintf( "The value of Pi is calculated to be %f.\n",  
                      M_PI);  
  
   size = count + 1; // the string will need one more char for the null terminator  
   s = malloc(sizeof(char) * size);  
   sprintf_s(s, size, "The value of Pi is calculated to be %f.\n",  
                      M_PI);  
   printf("The length of the following string will be %i.\n", count);  
   printf("%s", s);  
   free( s );  
}

The length of the following string will be 46.  
The value of Pi is calculated to be 3.141593.

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