我以 root 身份登录，无法看到其他人使用screen -ls.我认为 root 用户可以访问这些屏幕，但我找不到有用的屏幕选项：
Use: screen [-opts] [cmd [args]]
or: screen -r [host.tty]
Options:
-4 Use IPv4.
-6 Use IPv6.
-a Force all capabilities into each window's termcap.
-A -[r|R] Adapt all windows to the new display width & height.
-c file Read configuration file instead of '.screenrc'.
-d (-r) Detach the elsewhere running screen (and reattach here).
-dmS name Start as daemon: Screen session in detached mode.
-D (-r) Detach and logout remote (and reattach here).
-D -RR Do whatever is needed to get a screen session.
-e xy Change command characters.
-f Flow control on, -fn = off, -fa = auto.
-h lines Set the size of the scrollback history buffer.
-i Interrupt output sooner when flow control is on.
-l Login mode on (update /var/run/utmp), -ln = off.
-list or -ls. Do nothing, just list our SockDir.
-L Turn on output logging.
-m ignore $STY variable, do create a new screen session.
-O Choose optimal output rather than exact vt100 emulation.
-p window Preselect the named window if it exists.
-q Quiet startup. Exits with non-zero return code if unsuccessful.
-r Reattach to a detached screen process.
-R Reattach if possible, otherwise start a new session.
-s shell Shell to execute rather than $SHELL.
-S sockname Name this session <pid>.sockname instead of <pid>.<tty>.<host>.
-t title Set title. (window's name).
-T term Use term as $TERM for windows, rather than "screen".
-U Tell screen to use UTF-8 encoding.
-v Print "Screen version 4.00.03 (FAU) 23-Oct-06".
-wipe Do nothing, just clean up SockDir.
-x Attach to a not detached screen. (Multi display mode).
-X Execute <cmd> as a screen command in the specified session.
那么我应该使用哪个？
答案1
除非有问题的屏幕会话是使用 创建的multiuser on，否则您不能。即使您将SCREENDIR变量设置为指向其他用户的套接字目录，屏幕也会抱怨您不拥有该目录，并在您尝试使用它时退出。
当然，您可以简单地su向其他用户并以正常方式使用屏幕。
答案2
您可以通过以下方式查看机器上的所有屏幕：
ls -laR /var/run/screen/
这至少会列出具有屏幕会话的套接字以及拥有它的用户。如果您拥有套接字的权限，它也会列出该用户正在使用的所有屏幕。
从这里