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

# wcsncpy(3)

copy a fixed-size string of wide characters

## NAME

wcsncpy - copy a fixed-size string of wide characters

## LIBRARY

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

## SYNOPSIS

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

**wchar\_t \*wcsncpy(**size\_t n;                  **wchar\_t** *dest***\[restrict** *n***\],**                  **const wchar\_t \*restrict** *src***,**                  **size\_t** *n***);**

## DESCRIPTION

The **wcsncpy**() function is the wide-character equivalent of the [**strncpy**(3)](/strncpy/3.md) function. It copies at most *n* wide characters from the wide-character string pointed to by *src*, including the terminating null wide character (L'\\0'), to the array pointed to by *dest*. Exactly *n* wide characters are written at *dest*. If the length *wcslen(src)* is smaller than *n*, the remaining wide characters in the array pointed to by *dest* are filled with null wide characters. If the length *wcslen(src)* is greater than or equal to *n*, the string pointed to by *dest* will not be terminated by a null wide character.

The strings may not overlap.

The programmer must ensure that there is room for at least *n* wide characters at *dest*.

## RETURN VALUE

**wcsncpy**() returns *dest*.

## ATTRIBUTES

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

| | | |
| --- | --- | --- |
| **Interface** | **Attribute** | **Value** |
| **wcsncpy**() | Thread safety | MT-Safe |

## STANDARDS

C11, POSIX.1-2008.

## HISTORY

POSIX.1-2001, C99.

## SEE ALSO

[**strncpy**(3)](/strncpy/3.md)