ftruncate.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 1999 by Sun Microsystems, Inc.
* All rights reserved.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <syscall.h>
#include <sys/types.h>
/* The following are from SVR4 sys/fcntl.h */
#define F_FREESP 11 /* Free file space */
#define F_WRLCK 02 /* Write Lock */
/* lock structure from SVR4. */
struct fl {
short l_type;
short l_whence;
off_t l_start;
off_t l_len;
long l_sysid;
pid_t l_pid;
long pad[4];
};
int ftruncate(int fd, off_t length)
{
struct fl lck;
lck.l_whence = 0; /* offset l_start from beginning of file */
lck.l_start = length;
lck.l_type = F_WRLCK; /* setting a write lock */
lck.l_len = 0L;
if (_syscall(SYS_fcntl, fd, F_FREESP, (int)&lck) == -1)
return (-1);
else
return (0);
}