+++ /dev/null
-.\" 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.
-.\" 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.
-.\"
-.\" @(#)fseek.3 8.1 (Berkeley) 6/4/93
-.\" $FreeBSD: src/lib/libc/stdio/fseek.3,v 1.27 2007/06/18 02:13:04 ache Exp $
-.\"
-.Dd March 19, 2004
-.Dt FSEEK 3
-.Os
-.Sh NAME
-.Nm fgetpos ,
-.Nm fseek ,
-.Nm fseeko ,
-.Nm fsetpos ,
-.Nm ftell ,
-.Nm ftello ,
-.Nm rewind
-.Nd reposition a stream
-.Sh LIBRARY
-.Lb libc
-.Sh SYNOPSIS
-.In stdio.h
-.Ft int
-.Fo fgetpos
-.Fa "FILE *restrict stream"
-.Fa "fpos_t *restrict pos"
-.Fc
-.Ft int
-.Fo fseek
-.Fa "FILE *stream"
-.Fa "long offset"
-.Fa "int whence"
-.Fc
-.Ft int
-.Fo fseeko
-.Fa "FILE *stream"
-.Fa "off_t offset"
-.Fa "int whence"
-.Fc
-.Ft int
-.Fo fsetpos
-.Fa "FILE *stream"
-.Fa "const fpos_t *pos"
-.Fc
-.Ft long
-.Fo ftell
-.Fa "FILE *stream"
-.Fc
-.Ft off_t
-.Fo ftello
-.Fa "FILE *stream"
-.Fc
-.Ft void
-.Fo rewind
-.Fa "FILE *stream"
-.Fc
-.Sh DESCRIPTION
-The
-.Fn fseek
-function sets the file position indicator for the stream pointed
-to by
-.Fa stream .
-The new position, measured in bytes, is obtained by adding
-.Fa offset
-bytes to the position specified by
-.Fa whence .
-If
-.Fa whence
-is set to
-.Dv SEEK_SET ,
-.Dv SEEK_CUR ,
-or
-.Dv SEEK_END ,
-the offset is relative to the
-start of the file, the current position indicator, or end-of-file,
-respectively.
-A successful call to the
-.Fn fseek
-function clears the end-of-file indicator for the stream and undoes
-any effects of the
-.Xr ungetc 3
-and
-.Xr ungetwc 3
-functions on the same stream.
-.Pp
-The
-.Fn ftell
-function
-obtains the current value of the file position indicator for the
-stream pointed to by
-.Fa stream .
-.Pp
-The
-.Fn rewind
-function sets the file position indicator for the stream pointed
-to by
-.Fa stream
-to the beginning of the file.
-It is equivalent to:
-.Pp
-.Dl (void)fseek(stream, 0L, SEEK_SET)
-.Pp
-except that the error indicator for the stream is also cleared
-(see
-.Xr clearerr 3 ) .
-.Pp
-Since
-.Fn rewind
-does not return a value,
-an application wishing to detect errors should clear
-.Va errno ,
-then call
-.Fn rewind ,
-and if
-.Va errno
-is non-zero, assume an error has occurred.
-.Pp
-The
-.Fn fseeko
-function is identical to
-.Fn fseek ,
-except it takes an
-.Fa off_t
-argument
-instead of a
-.Fa long .
-Likewise, the
-.Fn ftello
-function is identical to
-.Fn ftell ,
-except it returns an
-.Fa off_t .
-.Pp
-The
-.Fn fgetpos
-and
-.Fn fsetpos
-functions
-are alternate interfaces for retrieving and setting the current position in
-the file, similar to
-.Fn ftell
-and
-.Fn fseek ,
-except that the current position is stored in an opaque object of
-type
-.Vt fpos_t
-pointed to by
-.Fa pos .
-These functions provide a portable way to seek to offsets larger than
-those that can be represented by a
-.Vt long int .
-They may also store additional state information in the
-.Vt fpos_t
-object to facilitate seeking within files containing multibyte
-characters with state-dependent encodings.
-Although
-.Vt fpos_t
-has traditionally been an integral type,
-applications cannot assume that it is;
-in particular, they must not perform arithmetic on objects
-of this type.
-.Pp
-If the stream is a wide character stream (see
-.Xr fwide 3 ) ,
-the position specified by the combination of
-.Fa offset
-and
-.Fa whence
-must contain the first byte of a multibyte sequence.
-.Sh RETURN VALUES
-The
-.Fn rewind
-function
-returns no value.
-.Pp
-.Rv -std fgetpos fseek fseeko fsetpos
-.Pp
-Upon successful completion,
-.Fn ftell
-and
-.Fn ftello
-return the current offset.
-Otherwise, \-1 is returned and the global variable
-.Va errno
-is set to indicate the error.
-.Sh ERRORS
-.Bl -tag -width Er
-.It Bq Er EBADF
-The
-.Fa stream
-argument
-is not a seekable stream.
-.It Bq Er EINVAL
-The
-.Fa whence
-argument is invalid or
-the resulting file-position
-indicator would be set to a negative value.
-.It Bq Er EOVERFLOW
-The resulting file offset would be a value which
-cannot be represented correctly in an object of type
-.Fa off_t
-for
-.Fn fseeko
-and
-.Fn ftello
-or
-.Fa long
-for
-.Fn fseek
-and
-.Fn ftell .
-.It Bq Er ESPIPE
-The file descriptor underlying stream is associated with a pipe or FIFO
-or file-position indicator value is unspecified
-(see
-.Xr ungetc 3 ) .
-.El
-.Pp
-The functions
-.Fn fgetpos ,
-.Fn fseek ,
-.Fn fseeko ,
-.Fn fsetpos ,
-.Fn ftell ,
-.Fn ftello ,
-and
-.Fn rewind
-may also fail and set
-.Va errno
-for any of the errors specified for the routines
-.Xr fflush 3 ,
-.Xr fstat 2 ,
-.Xr lseek 2 ,
-and
-.Xr malloc 3 .
-.Sh LEGACY SYNOPSIS
-.Fd #include <stdio.h>
-.Fd #include <sys/types.h>
-.Pp
-.Ft int
-.br
-.Fo fseeko
-.Fa "FILE *stream"
-.Fa "off_t offset"
-.Fa "int whence"
-.Fc ;
-.Pp
-The include file
-.In sys/types.h
-supplies the definition for
-.Vt off_t .
-.Sh SEE ALSO
-.Xr lseek 2 ,
-.Xr clearerr 3 ,
-.Xr fwide 3 ,
-.Xr ungetc 3 ,
-.Xr ungetwc 3 ,
-.Xr compat 5
-.Sh STANDARDS
-The
-.Fn fgetpos ,
-.Fn fsetpos ,
-.Fn fseek ,
-.Fn ftell ,
-and
-.Fn rewind
-functions
-conform to
-.St -isoC .
-.Pp
-The
-.Fn fseeko
-and
-.Fn ftello
-functions conform to
-.St -p1003.1-2001 .
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