sunlabel(8)?
I found it in the base.tgz file. I managed to extract it to one of
the other system drives but it doesn't run:
# mount /dev/sd3c /mnt2
# mount_cd9660 /dev/cd0a /mnt
# cd /mnt2; mkdir cddata ; cd cddata
# tar -xzf /mnt/sparc/binary/sets/base.tgz "./usr/sbin/sunlabel"
./usr/sbin/sunlabel
# cd /mnt2/cddata/usr/sbin/
# ./sunlabel
sh: sunlabel: not found
Not found? It's right there unless I missed something.
I don't see any ls or equivalent confirming that it is, though what you
quote certainly looks to me as though it should be. I do note that
it's "sh: sunlabel: not found" rather than "sh: ./sunlabel: not found",
though I don't know enough to know whether that's significant. It
strikes me that this could be a missing library; on a 5.1 machine I
have handy (I don't see anything saying what OS rev you're at) sunlabel
is linked dynamic with -ltermcap and -lutil as well as -lc, and I don't
know whether any of those are available in .so form on the install
pseudo-live-CD system.
If the disk label is the only thing that got destroyed, you should be
able to mount /dev/sd3c if your root partition begins at the beginning
of the disk. Of course, if you split your system up into a lot of
partitions, just mounting root may not get you all that much. (If it
doesn't work, then recovering the partition table will be only half
your battle, since your filesystem is either corrupted or not in the
usual place.)