1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 23 /* All Rights Reserved */ 24 25 26 /* 27 * University Copyright- Copyright (c) 1982, 1986, 1988 28 * The Regents of the University of California 29 * All Rights Reserved 30 * 31 * University Acknowledgment- Portions of this document are derived from 32 * software developed by the University of California, Berkeley, and its 33 * contributors. 34 */ 35 36 /* 37 * lock a file pointer 38 */ 39 40 #include <stdio.h> 41 #include <string.h> 42 #include <fcntl.h> 43 44 int 45 lock(FILE *fp, char *mode, int blk) 46 { 47 struct flock l; 48 49 l.l_type = !strcmp(mode, "r") ? F_RDLCK : F_WRLCK; 50 l.l_whence = 0; 51 l.l_start = l.l_len = 0L; 52 return fcntl(fileno(fp), blk ? F_SETLKW : F_SETLK, &l); 53 } 54