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



PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (con-
       sult 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  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 st_atime field of the file associated with stream for update. The st_atime field shall
       be marked for update by the first successful execution  of  fgetc(),  fgets(),  fgetwc(),  fgetws(),  fread(),  fscanf(),
       getc(),  getchar(),  gets(),  or  scanf()  using  stream  that  returns  data not supplied by a prior call to ungetc() or
       ungetwc().

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 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  process  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 process is ignoring or blocking the SIGTTIN signal or the  process  group  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
       feof(), ferror(), fopen(), the Base Definitions volume of IEEE Std 1003.1-2001, <stdio.h>, <wchar.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003  Edition,  Standard  for
       Information  Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copy-
       right (C) 2001-2003 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.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                                    FGETWC(3P)