Originální popis anglicky:
fgetwc - get a wide-character code from a stream
Návod, kniha: POSIX Programmer's Manual
#include <stdio.h>
#include <wchar.h>
wint_t fgetwc(FILE *
stream);
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().
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.
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.
None.
The
ferror() or
feof() functions must be used to distinguish
between an error condition and an end-of-file condition.
None.
None.
feof() ,
ferror() ,
fopen() , the Base Definitions volume
of IEEE Std 1003.1-2001,
<stdio.h>,
<wchar.h>
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
.
