close.md

description	title	ms.date	api_name	api_location	api_type	topic_type	f1_keywords	helpviewer_keywords	ms.assetid
Learn more about: _close	_close	4/2/2020	_close _o__close	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	DLLExport	apiref	_close	_close function close function files [C++], closing	4708a329-8acf-4cd9-b7b0-a952e1897247

_close

Closes a file.

Syntax

int _close(
   int fd
);

Parameters

fd
File descriptor referring to the open file.

Return value

_close returns 0 if the file was successfully closed. A return value of -1 indicates an error.

Remarks

The _close function closes the file associated with fd.

The file descriptor and the underlying OS file handle are closed. Thus, it isn't necessary to call CloseHandle if the file was originally opened using the Win32 function CreateFile and converted to a file descriptor using _open_osfhandle.

This function validates its parameters. If fd is a bad file descriptor, the invalid parameter handler is invoked, as described in Parameter validation. If execution is allowed to continue, the functions returns -1 and errno is set to EBADF.

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

Requirements

Routine	Required header	Optional header
_close	<io.h>	<errno.h>

For more compatibility information, see Compatibility.

Example

See the example for _open.

See also

Low-level I/O
_chsize
_creat, _wcreat
_dup, _dup2
_open, _wopen
_unlink, _wunlink