1.\" $NetBSD: end.3,v 1.6 1996/10/16 17:20:30 perry Exp $ 2.\" 3.\" Copyright (c) 1986 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)end.3 6.4 (Berkeley) 1/24/94 35.\" 36.Dd October 16, 1996 37.Dt END 3 38.Os 39.Sh NAME 40.Nm end , 41.Nm etext , 42.Nm edata 43.Nd end boundaries of image segments 44.Sh SYNOPSIS 45.Vt extern end; 46.Vt extern etext; 47.Vt extern edata; 48.Sh DESCRIPTION 49The globals 50.Va end , etext 51and 52.Va edata 53are program segment end addresses. 54.Pp 55.Va etext 56is the first address after the end of the text segment. 57.Pp 58.Va edata 59is the first address after the end of the initialized data segment. 60.Pp 61.Va end 62is the first address after the end of the data segment 63.Pq Tn BSS 64when the program is loaded. Use the 65.Xr sbrk 2 66.\".Fn sbrk 0 67system call with zero as its argument to find the current end of the 68data segment. 69.Sh SEE ALSO 70.Xr sbrk 2 , 71.Xr malloc 3 , 72.Xr a.out 5 73.Sh HISTORY 74An 75.Nm end 76manual page appeared in 77.At v6 . 78.Sh BUGS 79Traditionally, no variable existed that pointed to the start of the 80text segment because the text segment always started at address 81zero. Although it is no longer valid to make this assumption, no 82variable similar to the ones documented above exists to point to the 83start of the text segment. 84