xref: /freebsd/lib/libc/gen/getbootfile.3 (revision 4b9d605768acabc460aa6dcfe8a1f8db35b16794)
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28.Dd September 23, 1994
29.Dt GETBOOTFILE 3
30.Os
31.Sh NAME
32.Nm getbootfile
33.Nd get kernel boot file name
34.Sh LIBRARY
35.Lb libc
36.Sh SYNOPSIS
37.In paths.h
38.Ft const char *
39.Fn getbootfile void
40.Sh DESCRIPTION
41The
42.Fn getbootfile
43function retrieves the full pathname of the file from which the
44current kernel was loaded, and returns a static pointer to the name.
45A read/write interface to this information is available via the
46.Xr sysctl 3
47MIB variable
48.Dq Li kern.bootfile .
49.Sh RETURN VALUES
50If the call succeeds a string giving the pathname is returned.
51If it
52fails, a null pointer is returned and an error code is
53placed in the global location
54.Va errno .
55.Sh SEE ALSO
56.Xr sysctl 3
57.Sh HISTORY
58The
59.Fn getbootfile
60function appeared in
61.Fx 2.0 .
62.Sh BUGS
63If the boot blocks have not been modified to pass this information into
64the kernel at boot time, the static string
65.Dq Pa /boot/kernel/kernel
66is returned instead of the real boot file.
67