screen: Umask
8.4.7 aclumask
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-- Command: aclumask [USERS]+/-BITS ...
-- Command: umask [USERS]+/-BITS ...
(none)
This specifies the access other users have to windows that will be
created by the caller of the command. USERS may be no, one or a
comma separated list of known usernames. If no users are
specified, a list of all currently known users is assumed. BITS is
any combination of access control bits allowed defined with the
'aclchg' command. The special username '?' predefines the access
that not yet known users will be granted to any window initially.
The special username '??' predefines the access that not yet known
users are granted to any command. Rights of the special username
nobody cannot be changed (see the 'su' command). 'Umask' is a
synonym to 'aclumask'.