xref: /freebsd/lib/libc/gen/getbootfile.3 (revision a0409676120c1e558d0ade943019934e0f15118d)
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28.\"     From: @(#)gethostname.3	8.1 (Berkeley) 6/4/93
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31.Dd September 23, 1994
32.Dt GETBOOTFILE 3
33.Os
34.Sh NAME
35.Nm getbootfile
36.Nd get kernel boot file name
37.Sh LIBRARY
38.Lb libc
39.Sh SYNOPSIS
40.In paths.h
41.Ft const char *
42.Fn getbootfile void
43.Sh DESCRIPTION
44The
45.Fn getbootfile
46function retrieves the full pathname of the file from which the
47current kernel was loaded, and returns a static pointer to the name.
48A read/write interface to this information is available via the
49.Xr sysctl 3
50MIB variable
51.Dq Li kern.bootfile .
52.Sh RETURN VALUES
53If the call succeeds a string giving the pathname is returned.
54If it
55fails, a null pointer is returned and an error code is
56placed in the global location
57.Va errno .
58.Sh SEE ALSO
59.Xr sysctl 3
60.Sh HISTORY
61The
62.Fn getbootfile
63function appeared in
64.Fx 2.0 .
65.Sh BUGS
66If the boot blocks have not been modified to pass this information into
67the kernel at boot time, the static string
68.Dq Pa /boot/kernel/kernel
69is returned instead of the real boot file.
70