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.\"     From: @(#)gethostname.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/gen/getbootfile.3,v 1.6.2.3 2001/12/14 18:33:51 ru Exp $
.\" $DragonFly: src/lib/libc/gen/getbootfile.3,v 1.2 2003/06/17 04:26:42 dillon Exp $
.\"
.Dd September 23, 1994
.Dt GETBOOTFILE 3
.Os
.Sh NAME
.Nm getbootfile
.Nd get kernel boot file name
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In paths.h
.Ft const char *
.Fn getbootfile void
.Sh DESCRIPTION
The
.Fn getbootfile
function retrieves the full pathname of the file from which the
current kernel was loaded, and returns a static pointer to the name.
A read/write interface to this information is available via the
.Xr sysctl 3
MIB variable
.Dq Li kern.bootfile .
.Sh RETURN VALUES
If the call succeeds a string giving the pathname is returned.  If it
fails, a null pointer is returned and an error code is
placed in the global location
.Va errno .
.Sh SEE ALSO
.Xr sysctl 3
.Sh BUGS
If the boot blocks have not been modified to pass this information into
the kernel at boot time, the static string
.Dq Pa /kernel
is returned instead of the real boot file.
.Sh HISTORY
The
.Fn getbootfile
function call appeared in
.Fx 2.0 .