fflush-nolock.md

title	_fflush_nolock
description	Learn more about: _fflush_nolock
ms.date	4/2/2020
api_name	_fflush_nolock _o__fflush_nolock
api_location	msvcrt.dll msvcr80.dll msvcr90.dll msvcr100.dll msvcr100_clr0400.dll msvcr110.dll msvcr110_clr0400.dll msvcr120.dll msvcr120_clr0400.dll ucrtbase.dll api-ms-win-crt-stdio-l1-1-0.dll
api_type	DLLExport
topic_type	apiref
f1_keywords	fflush_nolock _fflush_nolock
helpviewer_keywords	fflush_nolock function _fflush_nolock function streams, flushing flushing

_fflush_nolock

Flushes a stream without locking.

Syntax

int _fflush_nolock(
   FILE *stream
);

Parameters

stream
Pointer to the FILE structure.

Return value

See fflush.

Remarks

This function is a non-locking version of fflush. It's identical to fflush except that it isn't protected from interference by other threads. It might be faster because it doesn't incur the overhead of locking out other threads. Use this function only in thread-safe contexts such as single-threaded applications or where the calling scope already handles thread isolation.

By default, this function's global state is scoped to the application. To change this behavior, see Global state in the CRT.

Requirements

Function	Required header
_fflush_nolock	<stdio.h>

For more compatibility information, see Compatibility.

See also

Stream I/O
fclose, _fcloseall
_flushall
setvbuf