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.\" Copyright (c) 1986
.\" The Regents of the University of California. All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the University of
.\" California, Berkeley and its contributors.
.\" 4. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" @(#)end.3 6.4 (Berkeley) 1/24/94
.\" $FreeBSD$
.\"
.Dd August 28, 2000
.Dt END 3
.Os
.Sh NAME
.Nm end ,
.Nm etext ,
.Nm edata
.Nd end boundaries of image segments
.Sh SYNOPSIS
.Vt extern end ;
.Vt extern etext ;
.Vt extern edata ;
.Sh DESCRIPTION
The globals
.Va end , etext
and
.Va edata
are program segment end addresses.
.Pp
.Va etext
is the first address after the end of the text segment.
.Pp
.Va edata
is the first address after the end of the initialized data segment.
.Pp
.Va end
is the first address after the end of the data segment
.Pq Tn BSS
when the program is loaded.
Use the
.Xr sbrk 2
.\".Fn sbrk 0
system call with zero as its argument to find the current end of the
data segment.
.Sh SEE ALSO
.Xr sbrk 2 ,
.Xr malloc 3 ,
.Xr a.out 5
.Sh HISTORY
An
.Nm
manual page appeared in
.At v6 .
.Sh BUGS
Traditionally, no variable existed that pointed to the start of the
text segment because the text segment always started at address zero.
Although it is no longer valid to make this assumption, no
variable similar to the ones documented above exists to point to the
start of the text segment.
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