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vprintf, _vprintf_l, vwprintf, _vwprintf_l

Write formatted output 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.

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 noteSecurity Note:

Ensure that format is not a user-defined string. For more information, see Avoiding Buffer Overruns. The risk of using user-defined strings is much less in Visual C++ 2005, because 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.

For additional compatibility information, see Compatibility in the Introduction.

.NET Framework Equivalent

System::Console::Write

See Also

Concepts

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_end, va_start