screen: At
20.1 At
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-- Command: at [identifier][#|*|%] command [args]
(none)
Execute a command at other displays or windows as if it had been
entered there. 'At' changes the context (the 'current window' or
'current display' setting) of the command. If the first parameter
describes a non-unique context, the command will be executed
multiple times. If the first parameter is of the form
'IDENTIFIER*' then identifier is matched against user names. The
command is executed once for each display of the selected user(s).
If the first parameter is of the form 'IDENTIFIER%' identifier is
matched against displays. Displays are named after the ttys they
attach. The prefix '/dev/' or '/dev/tty' may be omitted from the
identifier. If IDENTIFIER has a '#' or nothing appended it is
matched against window numbers and titles. Omitting an identifier
in front of the '#', '*' or '%' character selects all users,
displays or windows because a prefix-match is performed. Note that
on the affected display(s) a short message will describe what
happened. Note that the '#' character works as a comment
introducer when it is preceded by whitespace. This can be escaped
by prefixing '#' with a '\'. Permission is checked for the
initiator of the 'at' command, not for the owners of the affected
display(s). Caveat: When matching against windows, the command is
executed at least once per window. Commands that change the
internal arrangement of windows (like 'other') may be called again.
In shared windows the command will be repeated for each attached
display. Beware, when issuing toggle commands like 'login'! Some
commands (e.g. '\*Qprocess') require that a display is associated
with the target windows. These commands may not work correctly
under 'at' looping over windows.