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

       fgetwc — get a wide-character code from a stream

SYNOPSIS

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

       wint_t fgetwc(FILE *stream);

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.1‐2008 defers to the ISO C standard.

       The  fgetwc()  function shall obtain the next character (if present) from the input stream
       pointed to by stream, convert that to the corresponding wide-character code,  and  advance
       the associated file position indicator for the stream (if defined).

       If  an  error occurs, the resulting value of the file position indicator for the stream is
       unspecified.

       The fgetwc() function may mark the last data access timestamp of the file associated  with
       stream  for update. The last data access timestamp shall be marked for update by the first
       successful execution of fgetwc(), fgetws(), fwscanf(),  getwc(),  getwchar(),  vfwscanf(),
       vwscanf(),  or  wscanf()  using  stream  that returns data not supplied by a prior call to
       ungetwc().

       The fgetwc() function shall not change the setting of errno if successful.

RETURN VALUE

       Upon successful completion, the fgetwc() function shall return the wide-character code  of
       the  character read from the input stream pointed to by stream converted to a type wint_t.
       If the end-of-file indicator for the stream is set, or if the stream  is  at  end-of-file,
       the end-of-file indicator for the stream shall be set and fgetwc() shall return WEOF. If a
       read error occurs, the error indicator for the stream shall be set, fgetwc() shall  return
       WEOF,  and  shall set errno to indicate the error.  If an encoding error occurs, the error
       indicator for the stream shall be set, fgetwc() shall return WEOF, and shall set errno  to
       indicate the error.

ERRORS

       The fgetwc() function shall fail if data needs to be read and:

       EAGAIN The O_NONBLOCK flag is set for the file descriptor underlying stream and the thread
              would be delayed in the fgetwc() operation.

       EBADF  The file descriptor underlying stream is not  a  valid  file  descriptor  open  for
              reading.

       EILSEQ The data obtained from the input stream does not form a valid character.

       EINTR  The  read  operation was terminated due to the receipt of a signal, and no data was
              transferred.

       EIO    A physical I/O error has occurred, or the process is in a background process  group
              attempting  to read from its controlling terminal, and either the calling thread is
              blocking SIGTTIN or the process is ignoring SIGTTIN or the  process  group  of  the
              process  is  orphaned.  This error may also be generated for implementation-defined
              reasons.

       EOVERFLOW
              The file is a regular file and an attempt was made to read at or beyond the  offset
              maximum associated with the corresponding stream.

       The fgetwc() function may fail if:

       ENOMEM Insufficient storage space is available.

       ENXIO  A  request  was  made  of  a  nonexistent  device,  or  the request was outside the
              capabilities of the device.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       The ferror() or feof() functions must be used to distinguish between  an  error  condition
       and an end-of-file condition.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       Section 2.5, Standard I/O Streams, feof(), ferror(), fopen()

       The Base Definitions volume of POSIX.1‐2008, <stdio.h>, <wchar.h>

COPYRIGHT

       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 .

       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 .