-.TH FSEEK 3 "April 1, 1989"
-.AT 3
-.SH NAME
-fseek, ftell, rewind \- reposition a stream
-.SH SYNOPSIS
-.B #include <stdio.h>
-.PP
-.B fseek(stream, offset, ptrname)
-.br
-.SM
-.B FILE
-.B *stream;
-.br
-.B long offset;
-.PP
-.B long ftell(stream)
-.br
-.SM
-.B FILE
-.B *stream;
-.PP
-.B rewind(stream)
-.SH DESCRIPTION
-.I Fseek
-sets the position of the next input or output
-operation on the
-.IR stream .
-The new position is at the signed distance
-.I offset
-bytes
-from the beginning, the current position, or the end of the file,
-according as
-.I ptrname
-has the value 0, 1, or 2.
-.PP
-.I Fseek
-undoes any effects of
-.IR ungetc (3).
-.PP
-.I Ftell
-returns the current value of the offset relative to the beginning
-of the file associated with the named
-.IR stream .
-It is measured in bytes on UNIX;
-on some other systems it is a magic cookie,
-and the only foolproof way to obtain an
-.I offset
-for
-.IR fseek .
-.PP
-.IR Rewind ( stream )
-is equivalent to
-.IR fseek ( stream ,
-0L, L_SET).
-.SH "SEE ALSO"
-lseek(2),
-fopen(3)
-.SH DIAGNOSTICS
-.I Fseek
-returns \-1 for improper seeks, otherwise zero.
+.\" 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.
+.\"
+.\" @(#)fseek.3 6.11 (Berkeley) 6/29/91
+.\"
+.Dd June 29, 1991
+.Dt FSEEK 3
+.Os
+.Sh NAME
+.Nm fgetpos ,
+.Nm fseek ,
+.Nm fsetpos ,
+.Nm ftell ,
+.Nm rewind
+.Nd reposition a stream
+.Sh SYNOPSIS
+.Fd #include <stdio.h>
+.Ft int
+.Fn fseek "FILE *stream" "long offset" "int whence"
+.Ft long
+.Fn ftell "FILE *stream"
+.Ft void
+.Fn rewind "FILE *stream"
+.Ft int
+.Fn fgetpos "FILE *stream" "fpos_t *pos"
+.Ft int
+.Fn fsetpos "FILE *stream" "fpos_t *pos"
+.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
+function 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
+The
+.Fn fgetpos
+and
+.Fn fsetpos
+functions
+are alternate interfaces equivalent to
+.Fn ftell
+and
+.Fn fseek
+(with whence set to
+.Dv SEEK_SET
+), setting and storing the current value of
+the file offset into or from the object referenced by
+.Fa pos .
+On some
+.Pq non- Ns Tn UNIX
+systems an
+.Dq Fa fpos_t
+object may be a complex object
+and these routines may be the only way to portably reposition a text stream.
+.Sh RETURN VALUES
+The
+.Fn rewind
+function
+returns no value.
+Upon successful completion,
+.Fn fgetpos ,
+.Fn fseek ,
+.Fn fsetpos
+return 0,
+and
+.Fn ftell
+returns the current offset.
+Otherwise, \-1 is returned and the global variable errno is set to
+indicate the error.
+.Sh ERRORS
+.Bl -tag -width [EINVAL]
+.It Bq Er EBADF
+The
+.Fa stream
+specified
+is not a seekable stream.
+.It Bq Er EINVAL
+The
+.Fa whence
+argument to
+.Fn fseek
+was not
+.Dv SEEK_SET ,
+.Dv SEEK_END ,
+or
+.Dv SEEK_CUR .
+.El
+.Pp
+The function
+.Fn fgetpos ,
+.Fn fseek ,
+.Fn fsetpos ,
+and
+.Fn ftell
+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 SEE ALSO
+.Xr lseek 2
+.Sh STANDARDS
+The
+.Fn fgetpos ,
+.Fn fsetpos ,
+.Fn fseek ,
+.Fn ftell ,
+and
+.Fn rewind
+functions
+conform to
+.St -ansiC .
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