— Command: acladd usernames
— Command: addacl usernames

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Enable users to fully access this screen session. Usernames can be one user or a comma separated list of users. This command enables to attach to the screen session and performs the equivalent of aclchg usernames +rwx "#?". To add a user with restricted access, use the aclchg command below. Addacl is a synonym to acladd. Multi-user mode only.