This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface

       None.

       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(3POSIX)

       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.

       No errors are defined.

       Thefollowingsectionsareinformative.

       None.

       None.

       btowc — single byte to wide character conversion

       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.

       None.

       The btowc() function shall return WEOF if c has the value EOF or if (unsignedchar)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.

wctob()

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

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

       wint_t btowc(int c);