This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the corresponding Linux
manual page for details of Linux behavior), or the interface may not be
implemented on Linux.
btowc — single byte to wide character conversion
wint_t btowc(int c);
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.1‐2008 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.
No errors are defined.
The following sections are informative.
The Base Definitions volume of POSIX.1‐2008,
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2013 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
7, Copyright (C) 2013 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. (This is POSIX.1-2008 with the 2013
Technical Corrigendum 1 applied.) In the event of any discrepancy between this
version and the original IEEE and The Open Group Standard, the original IEEE
and The Open Group Standard is the referee document. The original Standard can
be obtained online at http://www.unix.org/online.html .
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