2002-08-12 13:23:12 +00:00
|
|
|
.\" $NetBSD: ungetwc.3,v 1.3 2002/02/07 07:00:27 ross Exp $
|
|
|
|
|
.\"
|
|
|
|
|
.\" Copyright (c) 1990, 1991, 1993
|
|
|
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
|
|
|
.\"
|
|
|
|
|
.\" This code is derived from software contributed to Berkeley by
|
|
|
|
|
.\" Chris Torek and the American National Standards Committee X3,
|
|
|
|
|
.\" on Information Processing Systems.
|
|
|
|
|
.\"
|
|
|
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
|
|
|
.\" modification, are permitted provided that the following conditions
|
|
|
|
|
.\" are met:
|
|
|
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
|
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
|
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
|
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
|
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
|
|
|
.\" 3. All advertising materials mentioning features or use of this software
|
|
|
|
|
.\" must display the following acknowledgement:
|
|
|
|
|
.\" This product includes software developed by the University of
|
|
|
|
|
.\" California, Berkeley and its contributors.
|
|
|
|
|
.\" 4. Neither the name of the University nor the names of its contributors
|
|
|
|
|
.\" may be used to endorse or promote products derived from this software
|
|
|
|
|
.\" without specific prior written permission.
|
|
|
|
|
.\"
|
|
|
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
|
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
|
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
|
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
|
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
|
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
|
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
|
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
|
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
|
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
|
|
|
.\" SUCH DAMAGE.
|
|
|
|
|
.\"
|
|
|
|
|
.\" @(#)ungetc.3 8.1 (Berkeley) 6/4/93
|
|
|
|
|
.\" $FreeBSD$
|
|
|
|
|
.\"
|
|
|
|
|
.Dd October 24, 2001
|
|
|
|
|
.Dt UNGETWC 3
|
|
|
|
|
.Os
|
|
|
|
|
.Sh NAME
|
|
|
|
|
.Nm ungetwc
|
|
|
|
|
.Nd un-get wide-character from input stream
|
|
|
|
|
.Sh LIBRARY
|
|
|
|
|
.Lb libc
|
|
|
|
|
.Sh SYNOPSIS
|
2002-08-13 10:47:17 +00:00
|
|
|
.In stdio.h
|
|
|
|
|
.In wchar.h
|
2002-08-12 13:23:12 +00:00
|
|
|
.Ft wint_t
|
|
|
|
|
.Fn ungetwc "wint_t wc" "FILE *stream"
|
|
|
|
|
.Sh DESCRIPTION
|
|
|
|
|
The
|
|
|
|
|
.Fn ungetwc
|
|
|
|
|
function pushes the wide-character
|
|
|
|
|
.Fa wc
|
2002-12-04 17:49:15 +00:00
|
|
|
(converted to an
|
|
|
|
|
.Vt wchar_t )
|
2002-08-12 13:23:12 +00:00
|
|
|
back onto the input stream pointed to by
|
|
|
|
|
.Fa stream .
|
|
|
|
|
The pushed-backed wide-characters will be returned by subsequent reads on the
|
|
|
|
|
stream (in reverse order).
|
|
|
|
|
A successful intervening call, using the same stream, to one of the file
|
|
|
|
|
positioning functions
|
|
|
|
|
.Xr fseek 3 ,
|
|
|
|
|
.Xr fsetpos 3 ,
|
|
|
|
|
or
|
|
|
|
|
.Xr rewind 3
|
|
|
|
|
will discard the pushed back wide-characters.
|
|
|
|
|
.Pp
|
|
|
|
|
One wide-character of push-back is guaranteed,
|
|
|
|
|
but as long as there is
|
|
|
|
|
sufficient memory, an effectively infinite amount of pushback is allowed.
|
|
|
|
|
.Pp
|
|
|
|
|
If a character is successfully pushed-back,
|
|
|
|
|
the end-of-file indicator for the stream is cleared.
|
|
|
|
|
.Sh RETURN VALUES
|
|
|
|
|
The
|
|
|
|
|
.Fn ungetwc
|
|
|
|
|
function
|
|
|
|
|
returns
|
|
|
|
|
the wide-character pushed-back after the conversion, or
|
|
|
|
|
.Dv WEOF
|
|
|
|
|
if the operation fails.
|
|
|
|
|
If the value of the argument
|
|
|
|
|
.Fa c
|
|
|
|
|
character equals
|
|
|
|
|
.Dv WEOF ,
|
|
|
|
|
the operation will fail and the stream will remain unchanged.
|
|
|
|
|
.Sh SEE ALSO
|
|
|
|
|
.Xr fseek 3 ,
|
|
|
|
|
.Xr getwc 3
|
|
|
|
|
.Sh STANDARDS
|
|
|
|
|
The
|
|
|
|
|
.Fn ungetwc
|
|
|
|
|
function conforms to
|
2002-08-13 10:47:17 +00:00
|
|
|
.St -isoC-99 .
|
