huschi.net

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 (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 fgetwc() function shall obtain the next character (if present) from
       the  input stream pointed to by stream, convert that to the correspond-
       ing wide-character code, and advance the associated file position indi-
       cator 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  associ-
       ated  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()  opera-
              tion.
       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 sig-
              nal, and no data was transferred.
       EIO    A physical I/O error has occurred, or the process is in a  back-
              ground  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, Copyright (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.opengroup.org/unix/online.html .

IEEE/The Open Group                  2003                           FGETWC(3P)