1 /* @(#)fdup.c	1.16 10/11/06 Copyright 1986, 1995-2010 J. Schilling */
2 /*
3  *	Copyright (c) 1986, 1995-2010 J. Schilling
4  */
5 /*
6  * The contents of this file are subject to the terms of the
7  * Common Development and Distribution License, Version 1.0 only
8  * (the "License").  You may not use this file except in compliance
9  * with the License.
10  *
11  * See the file CDDL.Schily.txt in this distribution for details.
12  * A copy of the CDDL is also available via the Internet at
13  * http://www.opensource.org/licenses/cddl1.txt
14  *
15  * When distributing Covered Code, include this CDDL HEADER in each
16  * file and include the License file CDDL.Schily.txt from this distribution.
17  */
18 
19 #include "schilyio.h"
20 
21 /*
22  * Note that because of a definition in schilyio.h we are using
23  * fseeko()/ftello() instead of fseek()/ftell() if available.
24  */
25 
26 EXPORT FILE *
fdup(f)27 fdup(f)
28 	register FILE  *f;
29 {
30 	int  newfd;
31 
32 	down(f);
33 	if ((newfd = dup(fileno(f))) < 0)
34 		return ((FILE *)NULL);
35 
36 	lseek(newfd, ftell(f), SEEK_SET);
37 	return (_fcons((FILE *)0, newfd, (FI_READ | FI_WRITE | FI_CLOSE)));
38 }
39