freebsd-dev/share/man/man3/end.3

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.\"	@(#)end.3	6.4 (Berkeley) 1/24/94
.\" $FreeBSD$
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.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Although it is no longer valid to make this assumption, no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.