BTOWC(3) Library Functions Manual BTOWC(3)

NAME

btowc — single byte to wide character conversion

SYNOPSIS

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

wint_t btowc(int c);

DESCRIPTION

[CX] The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1-2024 defers to the ISO C standard.

The btowc () function shall determine whether c constitutes a valid (one-byte) character in the initial shift state.

The behavior of this function shall be affected by the LC_CTYPE category of the current locale.

RETURN VALUE

The btowc () function shall return WEOF if c has the value EOF or if (unsigned char) c does not constitute a valid (one-byte) character in the initial shift state. Otherwise, it shall return the wide-character representation of that character.

[CX] In the POSIX locale, btowc () shall not return WEOF if c has a value in the range 0 to 255 inclusive.