btowc - single byte to wide character conversion
wint_t btowc(int c);
[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.1-2017 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.
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.
No errors are defined.
XBD <stdio.h>, <wchar.h>
First released in Issue 5. Included for alignment with ISO/IEC 9899:1990/Amendment 1:1995 (E).
POSIX.1-2008, Technical Corrigendum 2, XSH/TC2-2008/0052  is applied.
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