port issue

        assert ret.retval == 0, f"write_validate failed for {f}"

    # Build gkfs_hosts_new.txt containing only d00 (remove d01).

    # d00.address is "iface:PORT" (e.g. "lo:15680"); extract the port and

    # match it against the URI written in the hosts file

    # ("ofi+sockets://127.0.0.1:PORT ...").  Each daemon gets a unique

    # ephemeral port so this is a reliable discriminator.

    old_hostfile = Path(d00.hostfile)

    new_hostfile = old_hostfile.parent / "gkfs_hosts_new.txt"

    d00_port = d00.address.split(":")[-1]

    with open(old_hostfile) as hf_in, open(new_hostfile, "w") as hf_out:

        for line in hf_in:

            # Keep lines that belong to d00; skip d01 and comment lines

            if d00.hostname in line and not line.startswith("#"):

            if not line.startswith("#") and f":{d00_port}" in line:

                hf_out.write(line)

    assert new_hostfile.exists(), "New hosts file was not created"

    assert new_hostfile.stat().st_size > 0, \

        f"New hosts file is empty; d00 port '{d00_port}' not found in {old_hostfile}"

    libdirs = gkfs_shell._patched_env["LD_LIBRARY_PATH"]

    search_path = ":".join(str(p) for p in gkfs_shell._search_paths)