---
name: "putwc"
section: "3"
platform: "linux"
package: "man-pages"
version: "6.19-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux", "freebsd", "macos"]
url: "https://new.carta.tech/fputwc"
---

# putwc(3)

write a wide character to a FILE stream

Part of [fputwc(3)](/fputwc/3.md).

## NAME

fputwc, putwc - write a wide character to a FILE stream

## LIBRARY

Standard C library (*libc*, *-lc*)

## SYNOPSIS

```
#include <stdio.h>
#include <wchar.h>
```

**wint\_t fputwc(wchar\_t** *wc***, FILE \****stream***);** **wint\_t putwc(wchar\_t** *wc***, FILE \****stream***);**

## DESCRIPTION

The **fputwc**() function is the wide-character equivalent of the [**fputc**(3)](/fputc/3.md) function. It writes the wide character *wc* to *stream*. If *ferror(stream)* becomes true, it returns **WEOF**. If a wide-character conversion error occurs, it sets *errno* to **EILSEQ** and returns **WEOF**. Otherwise, it returns *wc*.

The **putwc**() function or macro functions identically to **fputwc**(). It may be implemented as a macro, and may evaluate its argument more than once. There is no reason ever to use it.

For nonlocking counterparts, see [**unlocked\_stdio**(3)](/unlocked_stdio/3.md).

## RETURN VALUE

On success, **fputwc**() function returns *wc*. Otherwise, **WEOF** is returned, and *errno* is set to indicate the error.

## ERRORS

Apart from the usual ones, there is

- **EILSEQ**

  Conversion of *wc* to the stream's encoding fails.

## ATTRIBUTES

For an explanation of the terms used in this section, see [**attributes**(7)](/attributes/7.md).

| | | |
| --- | --- | --- |
| **Interface** | **Attribute** | **Value** |
| **fputwc**(), **putwc**() | Thread safety | MT-Safe |

## STANDARDS

C11, POSIX.1-2008.

## HISTORY

C99, POSIX.1-2001.

## NOTES

The behavior of **fputwc**() depends on the **LC\_CTYPE** category of the current locale.

In the absence of additional information passed to the [**fopen**(3)](/fopen/3.md) call, it is reasonable to expect that **fputwc**() will actually write the multibyte sequence corresponding to the wide character *wc*.

## SEE ALSO

[**fgetwc**(3)](/fgetwc/3.md), [**fputws**(3)](/fputws/3.md), [**unlocked\_stdio**(3)](/unlocked_stdio/3.md)