#!/bin/bash

snapshot="$1"
if [ -z "$snapshot" ]; then
	echo "FreeBSD/ZFS snapshot handling bug"
	echo ""
	echo "Usage: $0 <zfs snapshot>"
	exit 1
fi

snapshot="$(zfs list -t snapshot -H -o name "$snapshot")"
if [ -z "$snapshot" ]; then
	echo "Snapshot not found"
	exit 2
fi

dataset="${snapshot%@*}"
sn="${snapshot#*@}"
mountpoint=$(mount | grep "^$dataset[[:space:]]" | awk '{print $3}')

if [ ! -d "$mountpoint" ]; then
	echo "Could not determine mount point for $dataset"
	exit 3
fi

echo "** dataset=$dataset snapname=$sn mounted=$mountpoint"

(
cd "$mountpoint/.zfs/snapshot"
yes "$sn" | xargs stat > /dev/null
) &
(
#while : ; do zfs send -R "$snapshot" > /dev/null ; done
while : ; do umount "$mountpoint/.zfs/snapshot/$sn" 2>/dev/null ; done
)