xref: /freebsd/lib/libc/gen/getbootfile.3 (revision 4f8f43b06ed07e96a250855488cc531799d5b78f)
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28.\"     From: @(#)gethostname.3	8.1 (Berkeley) 6/4/93
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30.Dd September 23, 1994
31.Dt GETBOOTFILE 3
32.Os
33.Sh NAME
34.Nm getbootfile
35.Nd get kernel boot file name
36.Sh LIBRARY
37.Lb libc
38.Sh SYNOPSIS
39.In paths.h
40.Ft const char *
41.Fn getbootfile void
42.Sh DESCRIPTION
43The
44.Fn getbootfile
45function retrieves the full pathname of the file from which the
46current kernel was loaded, and returns a static pointer to the name.
47A read/write interface to this information is available via the
48.Xr sysctl 3
49MIB variable
50.Dq Li kern.bootfile .
51.Sh RETURN VALUES
52If the call succeeds a string giving the pathname is returned.
53If it
54fails, a null pointer is returned and an error code is
55placed in the global location
56.Va errno .
57.Sh SEE ALSO
58.Xr sysctl 3
59.Sh HISTORY
60The
61.Fn getbootfile
62function appeared in
63.Fx 2.0 .
64.Sh BUGS
65If the boot blocks have not been modified to pass this information into
66the kernel at boot time, the static string
67.Dq Pa /boot/kernel/kernel
68is returned instead of the real boot file.
69