[ahl 5.16.2007]
Due to a stale cache of ZFS shares in libshare, the second invocation of zfs_share_nfs() will fail here:
share = zfs_sa_find_share(hdl->libzfs_sharehdl, mountpoint);
This will return NULL for a share created after the initialization of libshare a few lines above. This was introduced by:
6491973 sharemgr: zfs set sharenfs=on is slow with lots of zfs filesystems