Libc-498.tar.gz

[apple/libc.git] / stdio / getwc.3

.\"	$NetBSD: getwc.3,v 1.3 2002/02/07 07:00:26 ross Exp $
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.\"     @(#)getc.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/stdio/getwc.3,v 1.6 2004/03/16 13:30:11 tjr Exp $
.\"
.Dd March 3, 2004
.Dt GETWC 3
.Os
.Sh NAME
.Nm fgetwc ,
.Nm getwc ,
.Nm getwchar
.Nd get next wide character from input stream
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In stdio.h
.In wchar.h
.Ft wint_t
.Fn fgetwc "FILE *stream"
.Ft wint_t
.Fn getwc "FILE *stream"
.Ft wint_t
.Fn getwchar void
.Sh DESCRIPTION
The
.Fn fgetwc
function
obtains the next input wide character (if present) from the stream pointed at by
.Fa stream ,
or the next character pushed back on the stream via
.Xr ungetwc 3 .
.Pp
The
.Fn getwc
function
acts essentially identically to
.Fn fgetwc .
.Pp
The
.Fn getwchar
function
is equivalent to
.Fn getwc
with the argument
.Dv stdin .
.Pp
Extended locale versions of these functions are documented in
.Xr getwc_l 3 .
See
.Xr xlocale 3
for more information.
.Sh RETURN VALUES
If successful, these routines return the next wide character
from the
.Fa stream .
If the stream is at end-of-file or a read error occurs,
the routines return
.Dv WEOF .
The routines
.Xr feof 3
and
.Xr ferror 3
must be used to distinguish between end-of-file and error.
If an error occurs, the global variable
.Va errno
is set to indicate the error.
The end-of-file condition is remembered, even on a terminal, and all
subsequent attempts to read will return
.Dv WEOF
until the condition is cleared with
.Xr clearerr 3 .
.Sh SEE ALSO
.Xr ferror 3 ,
.Xr fopen 3 ,
.Xr fread 3 ,
.Xr getc 3 ,
.Xr getwc_l 3 ,
.Xr putwc 3 ,
.Xr stdio 3 ,
.Xr ungetwc 3
.Sh STANDARDS
The
.Fn fgetwc ,
.Fn getwc ,
and
.Fn getwchar
functions
conform to
.St -isoC-99 .