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_cprintf, _cprintf_l, _cwprintf, _cwprintf_l

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Formats and prints to the console. More-secure versions are available; see _cprintf_s, _cprintf_s_l, _cwprintf_s, _cwprintf_s_l.

Important

This API cannot be used in applications that execute in the Windows Runtime. For more information, see CRT functions not supported in Universal Windows Platform apps.

Syntax

int _cprintf(
   const char * format [, argument_list]
);
int _cprintf_l(
   const char * format,
   _locale_t locale [, argument_list]
);
int _cwprintf(
   const wchar * format [, argument_list]
);
int _cwprintf_l(
   const wchar * format,
   _locale_t locale [, argument_list]
);

Parameters

format
Format-control string.

argument_list
Optional parameters for the format string.

locale
The locale to use.

Return value

The number of characters printed.

Remarks

These functions format and print a series of characters and values directly to the console, using the _putch function (_putwch for _cwprintf) to output characters. Each argument in argument_list (if any) is converted and output according to the corresponding format specification in format. The format argument uses the format specification syntax for printf and wprintf functions. Unlike the fprintf, printf, and sprintf functions, _cprintf and _cwprintf don't translate line-feed characters into carriage return-line feed (CR-LF) combinations when output.

An important distinction is that _cwprintf displays Unicode characters when used in Windows. Unlike _cprintf, _cwprintf uses the current console locale settings.

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.

_cprintf validates the format parameter. If format is a null pointer, the function invokes the invalid parameter handler, as described in Parameter validation. If execution is allowed to continue, the function returns -1 and sets errno to EINVAL.

Important

Ensure that format is not a user-defined string.

Starting in Windows 10 version 2004 (build 19041), the printf family of functions prints exactly representable floating point numbers according to the IEEE 754 rules for rounding. In previous versions of Windows, exactly representable floating point numbers ending in '5' would always round up. IEEE 754 states that they must round to the closest even digit (also known as "Banker's Rounding"). For example, both printf("%1.0f", 1.5) and printf("%1.0f", 2.5) should round to 2. Previously, 1.5 would round to 2 and 2.5 would round to 3. This change only affects exactly representable numbers. For example, 2.35 (which, when represented in memory, is closer to 2.35000000000000008) continues to round up to 2.4. Rounding done by these functions now also respects the floating point rounding mode set by fesetround. Previously, rounding always chose FE_TONEAREST behavior. This change only affects programs built using Visual Studio 2019 version 16.2 and later. To use the legacy floating point rounding behavior, link with legacy_stdio_float_rounding.obj.

Generic-text routine mappings

Tchar.h routine _UNICODE and _MBCS not defined _MBCS defined _UNICODE defined
_tcprintf _cprintf _cprintf _cwprintf
_tcprintf_l _cprintf_l _cprintf_l _cwprintf_l

Requirements

Routine Required header
_cprintf, _cprintf_l <conio.h>
_cwprintf, _cwprintf_l <conio.h>

For more compatibility information, see Compatibility.

Example

// crt_cprintf.c
// compile with: /c
// This program displays some variables to the console.

#include <conio.h>

int main( void )
{
    int         i = -16,
                h = 29;
    unsigned    u = 62511;
    char        c = 'A';
    char        s[] = "Test";

    // Note that console output does not translate \n as
    // standard output does. Use \r\n instead.
    //
    _cprintf( "%d  %.4x  %u  %c %s\r\n", i, h, u, c, s );
}

-16  001d  62511  A Test

See also

Console and port I/O
_cscanf, _cscanf_l, _cwscanf, _cwscanf_l
fprintf, _fprintf_l, fwprintf, _fwprintf_l
printf, _printf_l, wprintf, _wprintf_l
sprintf, _sprintf_l, swprintf, _swprintf_l, __swprintf_l
vfprintf, _vfprintf_l, vfwprintf, _vfwprintf_l
_cprintf_s, _cprintf_s_l, _cwprintf_s, _cwprintf_s_l
_cprintf_p, _cprintf_p_l, _cwprintf_p, _cwprintf_p_l
Format specification syntax: printf and wprintf functions