BSD 4_3_Net_2 release

[unix-history] / usr / src / lib / libc / stdio / fseek.3

diff --git a/usr/src/lib/libc/stdio/fseek.3 b/usr/src/lib/libc/stdio/fseek.3
index 71c22ed..cfc9bda 100644 (file)
--- a/usr/src/lib/libc/stdio/fseek.3
+++ b/usr/src/lib/libc/stdio/fseek.3
@@ -1,125 +1,188 @@
-.\" Copyright (c) 1990 The Regents of the University of California.
+.\" Copyright (c) 1990, 1991 The Regents of the University of California.

 .\" All rights reserved.
 .\"
 .\" This code is derived from software contributed to Berkeley by
 .\" All rights reserved.
 .\"
 .\" This code is derived from software contributed to Berkeley by

-.\" Chris Torek.
+.\" Chris Torek and the American National Standards Committee X3,
+.\" on Information Processing Systems.

 .\"
 .\"

-.\" %sccs.include.redist.man%
+.\" 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.

 .\"
 .\"

-.\"    @(#)fseek.3     6.8 (Berkeley) %G%
+.\" 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.

 .\"
 .\"

-.TH FSEEK 3 ""
-.UC 7
-.SH NAME
-fgetpos, fseek, fsetpos, ftell, rewind \- reposition a stream
-.SH SYNOPSIS
-.nf
-.ft B
-#include <stdio.h>
-
-int
-fseek(FILE *stream, long offset, int whence);
-
-long
-ftell(FILE *stream);
-
-void
-rewind(FILE *stream);
-
-int
-fgetpos(FILE *stream, fpos_t *pos);
-
-int
-fsetpos(FILE *stream, fpos_t *pos);
-.ft R
-.fi
-.SH DESCRIPTION
-.I Fseek
-sets the position of the next input or output
-operation on the given
-.IR stream .
-The new position is at the signed distance
-.I offset
-bytes from a specified point in the file depending on the
-value of 
-.IR whence .
+.\"     @(#)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 
 If 

-.I whence
-is set to SEEK_SET, SEEK_CUR, or SEEK_END, the offset is from the
-beginning, the current position, or the end of the file, respectively.
-.I Fseek
-undoes any effects of
-.IR ungetc .
-.PP
-.I Ftell
-returns the current value of the offset relative to the beginning
-of the file associated with the named
-.IR stream .
-.PP
-.IR Rewind
-is equivalent to ``fseek(stream, 0L, SEEK_SET)'', except the error
-indicator for the stream is cleared as well (see
-.IR clearerr (3)).
-.PP
-.I Fgetpos
+.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
 and

-.I fsetpos
+.Fn fsetpos
+functions

 are alternate interfaces equivalent to
 are alternate interfaces equivalent to

-.I ftell
+.Fn ftell

 and
 and

-.I fseek
-(with whence set to SEEK_SET), setting and storing the current value of
+.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 
 the file offset into or from the object referenced by 

-.IR pos .
-On some (non-UNIX) systems an ``fpos_t'' object may be a complex object
+.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.
 and these routines may be the only way to portably reposition a text stream.

-.SH "SEE ALSO"
-lseek(2)
-.SH "RETURN VALUE"
-.I Rewind
+.Sh RETURN VALUES
+The
+.Fn rewind
+function

 returns no value.
 Upon successful completion,
 returns no value.
 Upon successful completion,

-.IR fgetpos ,
-.IR fseek ,
-and
-.I fsetpos
+.Fn fgetpos ,
+.Fn fseek ,
+.Fn fsetpos

 return 0,
 and
 return 0,
 and

-.I ftell
+.Fn ftell

 returns the current offset.
 Otherwise, \-1 is returned and the global variable errno is set to
 indicate the error.
 returns the current offset.
 Otherwise, \-1 is returned and the global variable errno is set to
 indicate the error.

-.SH ERRORS
-.TP 15
-[EBADF]
-.I Stream
+.Sh ERRORS
+.Bl -tag -width [EINVAL]
+.It Bq Er EBADF
+The
+.Fa stream
+specified

 is not a seekable stream.
 is not a seekable stream.

-.TP
-[EINVAL]
+.It Bq Er EINVAL

 The
 The

-.I whence
+.Fa whence

 argument to 
 argument to 

-.I fseek
-was not SEEK_SET, SEEK_END, or SEEK_CUR.
-.PP
-.IR Fgetpos ,
-.IR fseek ,
-.IR fsetpos ,
+.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 
 and 

-.I ftell
+.Fn ftell

 may also fail and set
 may also fail and set

-.I errno
+.Va errno

 for any of the errors specified for the routines
 for any of the errors specified for the routines

-.IR fflush (3),
-.IR fstat (2),
-.IR lseek (2),
+.Xr fflush 3 ,
+.Xr fstat 2 ,
+.Xr lseek 2 ,

 and 
 and 

-.IR malloc (3).
-.SH STANDARDS
-.IR Fgetpos ,
-.IR fsetpos ,
-.IR fseek ,
-.IR ftell ,
+.Xr malloc 3 .
+.Sh SEE ALSO
+.Xr lseek 2
+.Sh STANDARDS
+The
+.Fn fgetpos ,
+.Fn fsetpos ,
+.Fn fseek ,
+.Fn ftell ,

 and
 and

-.IR rewind
-conform to ANSI X3.159-1989 (``ANSI C'').
+.Fn rewind
+functions
+conform to
+.St -ansiC .