xref: /freebsd/share/man/man3/end.3 (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
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28.Dd August 28, 2000
29.Dt END 3
30.Os
31.Sh NAME
32.Nm end ,
33.Nm etext ,
34.Nm edata
35.Nd end boundaries of image segments
36.Sh SYNOPSIS
37.Vt extern end ;
38.Vt extern etext ;
39.Vt extern edata ;
40.Sh DESCRIPTION
41The globals
42.Va end , etext
43and
44.Va edata
45are program segment end addresses.
46.Pp
47.Va etext
48is the first address after the end of the text segment.
49.Pp
50.Va edata
51is the first address after the end of the initialized data segment.
52.Pp
53.Va end
54is the first address after the end of the data segment
55.Pq Tn BSS
56when the program is loaded.
57Use the
58.Xr sbrk 2
59.\".Fn sbrk 0
60system call with zero as its argument to find the current end of the
61data segment.
62.Sh SEE ALSO
63.Xr sbrk 2 ,
64.Xr malloc 3 ,
65.Xr a.out 5
66.Sh HISTORY
67An
68.Nm
69manual page appeared in
70.At v6 .
71.Sh BUGS
72Traditionally, no variable existed that pointed to the start of the
73text segment because the text segment always started at address zero.
74Although it is no longer valid to make this assumption, no
75variable similar to the ones documented above exists to point to the
76start of the text segment.
77