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

       Since it may be implemented as a macro, getwc() may  treat  incorrectly  a  stream  argument  with  side-
       effects.  In  particular,  getwc(*f++)  does  not  necessarily  work as expected.  Therefore, use of this
       function is not recommended; fgetwc() should be used instead.

       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                                         GETWC(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  getwc() function shall be equivalent to fgetwc(), except that if it is implemented as a macro it may
       evaluate stream more than once, so the argument should never be an expression with side-effects.

       Refer to fgetwc().

       Thefollowingsectionsareinformative.

       None.

       None.

       getwc — get a wide character from a stream

       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.

       Refer to fgetwc().

Section2.5, StandardI/OStreams, fgetwc()

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

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

       wint_t getwc(FILE *stream);