/* * 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) 1996 by Sun Microsystems, Inc. * * Map in a read-only page of zeroes at location zero, for stupid * programs that think a null pointer is as good as a null string. * * Use: * LD_PRELOAD=0@0.so.1 program args ... * */ /* LINTLIBRARY */ #include #include #include #include #pragma init(__zero_at_zero) void __zero_at_zero() { int fd; if ((fd = open("/dev/zero", O_RDWR)) < 0) return; (void) mmap(0, 1, PROT_READ, MAP_PRIVATE|MAP_FIXED, fd, 0); (void) close(fd); }