---
name: "curs_scanw"
section: "3x"
platform: "macos"
package: "ncurses"
version: "79"
release: "macOS 26.5"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/curs_scanw/3x"
---

# curs\_scanw(3x)

convert formatted input from a curses window

## NAME

**scanw**, **wscanw**, **mvscanw**, **mvwscanw**, **vwscanw**, **vw\_scanw** - convert formatted input from a **curses** window

## SYNOPSIS

**#include \<curses.h\>**

**int scanw(char \*fmt, ...);**\
 **int wscanw(WINDOW \*win, char \*fmt, ...);**\
 **int mvscanw(int y, int x, char \*fmt, ...);**\
 **int mvwscanw(WINDOW \*win, int y, int x, char \*fmt, ...);**\
 **int vw\_scanw(WINDOW \*win, char \*fmt, va\_list varglist);**\
 **int vwscanw(WINDOW \*win, char \*fmt, va\_list varglist);**

## DESCRIPTION

The **scanw**, **wscanw** and **mvscanw** routines are analogous to **scanf** \[see [**scanf**(3)](/scanf/3.md)\].  The effect of these routines is as though **wgetstr** were called on the window, and the resulting line used as input for [**sscanf**(3)](/sscanf/3.md).  Fields which do not map to a variable in the *fmt* field are lost.

The **vwscanw** and **vw\_scanw** routines are analogous to **vscanf**. They perform a **wscanw** using a variable argument list. The third argument is a *va\_list*, a pointer to a list of arguments, as defined in **\<stdarg.h\>**.

## RETURN VALUE

**vwscanw** returns **ERR** on failure and an integer equal to the number of fields scanned on success.

Applications may use the return value from the **scanw**, **wscanw**, **mvscanw** and **mvwscanw** routines to determine the number of fields which were mapped in the call.

Functions with a "mv" prefix first perform a cursor movement using **wmove**, and return an error if the position is outside the window, or if the window pointer is null.

## PORTABILITY

The XSI Curses standard, Issue 4 describes these functions.  The function **vwscanw** is marked TO BE WITHDRAWN, and is to be replaced by a function **vw\_scanw** using the **\<stdarg.h\>** interface. The Single Unix Specification, Version 2 states that **vw\_scanw**  is preferred to **vwscanw** since the latter requires including **\<varargs.h\>**, which cannot be used in the same file as **\<stdarg.h\>**. This implementation uses **\<stdarg.h\>** for both, because that header is included in **\<curses.h**\>.

Both XSI and The Single Unix Specification, Version 2 state that these functions return ERR or OK. Since the underlying **scanf** can return the number of items scanned, and the SVr4 code was documented to use this feature, this is probably an editing error which was introduced in XSI, rather than being done intentionally. Portable applications should only test if the return value is ERR, since the OK value (zero) is likely to be misleading. One possible way to get useful results would be to use a "%n" conversion at the end of the format string to ensure that something was processed.

## SEE ALSO

**curses**(3X), **curs\_getstr**(3X), **curs\_printw**(3X), [**scanf**(3)](/scanf/3.md)