我正在尝试将 Ubuntu 18.04 升级到 20.04，但 do-release-upgrade 无法创建额外的屏幕并退出到 root 提示符。从根提示符退出时显示“屏幕：\0\0：没有这样的文件或目录。”有谁知道如何解决或解决方法？不胜感激。
sudo do-release-upgrade
Checking for a new Ubuntu release
Get:1 Upgrade tool signature [1,554 B]
Get:2 Upgrade tool [1,338 kB]
Fetched 1,340 kB in 0s (0 B/s)
authenticate 'focal.tar.gz' against 'focal.tar.gz.gpg'
extracting 'focal.tar.gz'
root@st1 Sun Apr 09 16:56:/tmp/ubuntu-release-upgrader-os_4px5i#
logout
screen: \0\0: No such file or directory
以下内容来自 dist-upgrade main.log
2023-04-09 16:58:27,233 INFO Using config files '['./DistUpgrade.cfg.bionic']'
2023-04-09 16:58:27,234 INFO uname information: 'Linux st1 4.15.0-122-generic #124-Ubuntu SMP Thu Oct 15 13:03:05 UTC 2020 x86_64'
2023-04-09 16:58:27,822 INFO apt version: '1.6.14'
2023-04-09 16:58:27,822 INFO python version: '3.6.9 (default, Mar 10 2023, 16:46:00)
[GCC 8.4.0]'
2023-04-09 16:58:27,828 INFO release-upgrader version '20.04.40' started
2023-04-09 16:58:27,844 INFO locale: 'en_US' 'UTF-8'
2023-04-09 16:58:30,917 DEBUG screen returned: ''
2023-04-09 16:58:30,917 INFO re-exec inside screen: '['screen', '-e', '\\0\\0', '-c', 'screenrc', '-S', 'ubuntu-release-upgrade-screen-window', '/tmp/ubuntu-release-upgrader-c36px3u_/focal', '--mode=server', '--frontend=DistUpgradeViewText']'