$ [man]ktrace[/man] -ty uname -a
FreeBSD raphael.local 9.0-CURRENT FreeBSD 9.0-CURRENT #0 r213322 22d6ef5-dirty Fri Oct 1 19:43:24 UTC 2010 holo@raphael.local:/a/objdir/a/dirty_build/sys/PHOENIX amd64
$ [man]kdump[/man]
40948 uname SCTL "kern.ostype"
40948 uname SCTL "kern.hostname"
40948 uname SCTL "kern.osrelease"
40948 uname SCTL "kern.version"
40948 uname SCTL "hw.machine"
$ export UNAME_m= UNAME_n= UNAME_r= UNAME_s= UNAME_v=
$ ktrace -ty uname -a
$ kdump
$ unset UNAME_m UNAME_n UNAME_r UNAME_s UNAME_v