Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
Export (0) Print
Expand All
Expand Minimize

_vcprintf_s, _vcprintf_s_l, _vcwprintf_s, _vcwprintf_s_l

Write formatted output to the console using a pointer to a list of arguments. These are versions of _vcprintf, _vcprintf_l, _vcwprintf, _vcwprintf_l with security enhancements as described in Security Features in the CRT.

int _vcprintf(
   const char* format,
   va_list argptr
int _vcprintf(
   const char* format,
   locale_t locale,
   va_list argptr
int _vcwprintf_s(
   const wchar_t* format,
   va_list argptr
int _vcwprintf_s_l(
   const wchar_t* format,
   locale_t locale,
   va_list argptr


Format specification.


Pointer to list of arguments.


The locale to use.

For more information, see Format Specifications.

The number of characters written, or a negative value if an output error occurs.

Like the non-secure version of these functions, if format is a null pointer, the invalid parameter handler is invoked, as described in Parameter Validation. Additionally, unlike the non-secure version of these functions, if format does not specify a valid format, an invalid parameter exception is generated. If execution is allowed to continue, these functions return

Each of these functions takes a pointer to an argument list, then formats and writes the given data to the console. _vcwprintf_s is the wide-character version of _vcprintf_s. It takes a wide-character string as an argument.

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

Security noteSecurity Note

Ensure that format is not a user-defined string. For more information, see Avoiding Buffer Overruns.

Generic-Text Routine Mappings

TCHAR.H routine

_UNICODE & _MBCS not defined

_MBCS defined

_UNICODE defined










Required header

Optional headers

_vcprintf_s, _vcprintf_s_l

<conio.h> and <stdarg.h>


_vcwprintf_s, _vcwprintf_s_l

<conio.h> or <wchar.h>, and <stdarg.h>


* Required for UNIX V compatibility.

For additional compatibility information, see Compatibility in the Introduction.

// crt_vcprintf_s.cpp
#include <conio.h>
#include <stdarg.h>

// An error formatting function used to print to the console.
int eprintf_s(const char* format, ...)
  va_list args;
  va_start(args, format);
  return _vcprintf_s(format, args);

int main()
   eprintf_s("  (%d:%d): Error %s%d : %s\n", 10, 23, "C", 2111,
           "<some error text>");
   eprintf_s("  (Related to symbol '%s' defined on line %d).\n",
           "<symbol>", 5 );
  (10,23): Error C2111 : <some error text>
  (Related to symbol '<symbol>' defined on line 5).

Community Additions

© 2015 Microsoft