BTOWC(3P)                  POSIX Programmer's Manual                 BTOWC(3P)

PROLOG
       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.

NAME
       btowc -- single byte to wide character conversion

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

       wint_t btowc(int c);

DESCRIPTION
       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.

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.

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

ERRORS
       No errors are defined.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       wctob()

       The Base Definitions volume of POSIX.1-2017, <stdio.h>, <wchar.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1-2017, Standard for Information Technology --
       Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the
       Institute of Electrical and Electronics Engineers, Inc and The Open
       Group.  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.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page are
       most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                  2017                            BTOWC(3P)