vprintf, _vprintf_l, vwprintf, _vwprintf_l

Writes formatted output by using a pointer to a list of arguments. More secure versions of these functions are available, see vprintf_s, _vprintf_s_l, vwprintf_s, _vwprintf_s_l.

int vprintf(
   const char *format,
   va_list argptr 
);
int _vprintf_l(
   const char *format,
   locale_t locale,
   va_list argptr 
);
int vwprintf(
   const wchar_t *format,
   va_list argptr 
);
int _vwprintf_l(
   const wchar_t *format,
   locale_t locale,
   va_list argptr 
);

Parameters

• format
  Format specification.

• argptr
  Pointer to list of arguments.

• locale
  The locale to use.

For more information, see Format Specifications.

Return Value

vprintf and vwprintf return the number of characters written, not including the terminating null character, or a negative value if an output error occurs. If format is a null pointer, or if the format string contains invalid formatting characters, the invalid parameter handler is invoked, as described in Parameter Validation. If execution is allowed to continue, the functions return -1 and set errno to EINVAL.

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

Remarks

Each of these functions takes a pointer to an argument list, then formats and writes the given data to stdout.

vwprintf is the wide-character version of vprintf; the two functions behave identically if the stream is opened in ANSI mode. vprintf doesn't currently support output into a UNICODE stream.

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.

Security Note
Ensure that format is not a user-defined string. For more information, see Avoiding Buffer Overruns. Note that invalid format strings are detected and result in an error.

Generic-Text Routine Mappings

TCHAR.H routine	_UNICODE & _MBCS not defined	_MBCS defined	_UNICODE defined
_vtprintf	vprintf	vprintf	vwprintf
_vtprintf_l	_vprintf_l	_vprintf_l	_vwprintf_l

Requirements

Routine	Required header	Optional headers
vprintf, _vprintf_l	<stdio.h> and <stdarg.h>	<varargs.h>*
vwprintf, _vwprintf_l	<stdio.h> or <wchar.h>, and <stdarg.h>	<varargs.h>*

* Required for UNIX V compatibility.

The console is not supported in Windows Store apps. The standard stream handles that are associated with the console—stdin, stdout, and stderr—must be redirected before C run-time functions can use them in Windows Store apps. For additional compatibility information, see Compatibility.

.NET Framework Equivalent

System::Console::Write

See Also

Reference

Stream I/O

vprintf Functions

fprintf, _fprintf_l, fwprintf, _fwprintf_l

printf, _printf_l, wprintf, _wprintf_l

sprintf, _sprintf_l, swprintf, _swprintf_l, __swprintf_l

va_arg, va_copy, va_end, va_start