xref: /freebsd/share/man/man3/end.3 (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
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28.\"	@(#)end.3	6.4 (Berkeley) 1/24/94
29.\" $FreeBSD$
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31.Dd August 28, 2000
32.Dt END 3
33.Os
34.Sh NAME
35.Nm end ,
36.Nm etext ,
37.Nm edata
38.Nd end boundaries of image segments
39.Sh SYNOPSIS
40.Vt extern end ;
41.Vt extern etext ;
42.Vt extern edata ;
43.Sh DESCRIPTION
44The globals
45.Va end , etext
46and
47.Va edata
48are program segment end addresses.
49.Pp
50.Va etext
51is the first address after the end of the text segment.
52.Pp
53.Va edata
54is the first address after the end of the initialized data segment.
55.Pp
56.Va end
57is the first address after the end of the data segment
58.Pq Tn BSS
59when the program is loaded.
60Use the
61.Xr sbrk 2
62.\".Fn sbrk 0
63system call with zero as its argument to find the current end of the
64data segment.
65.Sh SEE ALSO
66.Xr sbrk 2 ,
67.Xr malloc 3 ,
68.Xr a.out 5
69.Sh HISTORY
70An
71.Nm
72manual page appeared in
73.At v6 .
74.Sh BUGS
75Traditionally, no variable existed that pointed to the start of the
76text segment because the text segment always started at address zero.
77Although it is no longer valid to make this assumption, no
78variable similar to the ones documented above exists to point to the
79start of the text segment.
80