xref: /titanic_52/usr/src/lib/libbc/libc/stdio/common/ftell.c (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
1*7c478bd9Sstevel@tonic-gate /*
2*7c478bd9Sstevel@tonic-gate  * CDDL HEADER START
3*7c478bd9Sstevel@tonic-gate  *
4*7c478bd9Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*7c478bd9Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*7c478bd9Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*7c478bd9Sstevel@tonic-gate  * with the License.
8*7c478bd9Sstevel@tonic-gate  *
9*7c478bd9Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*7c478bd9Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*7c478bd9Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*7c478bd9Sstevel@tonic-gate  * and limitations under the License.
13*7c478bd9Sstevel@tonic-gate  *
14*7c478bd9Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*7c478bd9Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*7c478bd9Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*7c478bd9Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*7c478bd9Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*7c478bd9Sstevel@tonic-gate  *
20*7c478bd9Sstevel@tonic-gate  * CDDL HEADER END
21*7c478bd9Sstevel@tonic-gate  */
22*7c478bd9Sstevel@tonic-gate /*
23*7c478bd9Sstevel@tonic-gate  * Copyright 1986 Sun Microsystems, Inc.  All rights reserved.
24*7c478bd9Sstevel@tonic-gate  * Use is subject to license terms.
25*7c478bd9Sstevel@tonic-gate  */
26*7c478bd9Sstevel@tonic-gate 
27*7c478bd9Sstevel@tonic-gate /*      Copyright (c) 1984 AT&T */
28*7c478bd9Sstevel@tonic-gate /*        All Rights Reserved   */
29*7c478bd9Sstevel@tonic-gate 
30*7c478bd9Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"  /* from S5R2 1.2 */
31*7c478bd9Sstevel@tonic-gate 
32*7c478bd9Sstevel@tonic-gate /*LINTLIBRARY*/
33*7c478bd9Sstevel@tonic-gate /*
34*7c478bd9Sstevel@tonic-gate  * Return file offset.
35*7c478bd9Sstevel@tonic-gate  * Coordinates with buffering.
36*7c478bd9Sstevel@tonic-gate  */
37*7c478bd9Sstevel@tonic-gate #include <stdio.h>
38*7c478bd9Sstevel@tonic-gate 
39*7c478bd9Sstevel@tonic-gate extern long lseek();
40*7c478bd9Sstevel@tonic-gate 
41*7c478bd9Sstevel@tonic-gate long
42*7c478bd9Sstevel@tonic-gate ftell(iop)
43*7c478bd9Sstevel@tonic-gate register FILE *iop;
44*7c478bd9Sstevel@tonic-gate {
45*7c478bd9Sstevel@tonic-gate 	register long tres;
46*7c478bd9Sstevel@tonic-gate 	register int adjust;
47*7c478bd9Sstevel@tonic-gate 
48*7c478bd9Sstevel@tonic-gate 	if(iop->_cnt < 0)
49*7c478bd9Sstevel@tonic-gate 		iop->_cnt = 0;
50*7c478bd9Sstevel@tonic-gate 	if(iop->_flag & _IOREAD)
51*7c478bd9Sstevel@tonic-gate 		adjust = - iop->_cnt;
52*7c478bd9Sstevel@tonic-gate 	else if(iop->_flag & (_IOWRT | _IORW)) {
53*7c478bd9Sstevel@tonic-gate 		adjust = 0;
54*7c478bd9Sstevel@tonic-gate 		if(iop->_flag & _IOWRT && iop->_base &&
55*7c478bd9Sstevel@tonic-gate 					(iop->_flag & _IONBF) == 0)
56*7c478bd9Sstevel@tonic-gate 			adjust = iop->_ptr - iop->_base;
57*7c478bd9Sstevel@tonic-gate 	} else
58*7c478bd9Sstevel@tonic-gate 		return(-1);
59*7c478bd9Sstevel@tonic-gate 	tres = lseek(fileno(iop), 0L, 1);
60*7c478bd9Sstevel@tonic-gate 	if(tres >= 0)
61*7c478bd9Sstevel@tonic-gate 		tres += (long)adjust;
62*7c478bd9Sstevel@tonic-gate 	return(tres);
63*7c478bd9Sstevel@tonic-gate }
64