> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/man/string/wcswidth.3.md).

# wcswidth.3

`wcswidth` — 宽字符串占用的列位置数

## 名称

`wcswidth`

## 库

Lb libc

## 概要

`#include <wchar.h>`

```c
int
wcswidth(const wchar_t *pwcs, size_t n);
```

## 描述

`wcswidth` 函数确定 `pwcs` 的前 `n` 个字符所占用的列位置数，直至遇到空宽字符（`L'\0'`）为止。

## 返回值

若 `pwcs` 为空字符串（`L""`），`wcswidth` 函数返回 0；若遇到不可打印的宽字符，返回 -1；否则返回所占用的列位置数。

## 参见

iswprint(3), [wcwidth(3)](https://github.com/FreeBSD-Ask/freebsd-man-sc/tree/main/string/wcwidth.3.md)

## 标准

`wcswidth` 函数遵循 IEEE Std 1003.1-2001 ("POSIX.1")。


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