Interactive Command History
The Tcl shell programs keep a log of the commands that you type by using a history facility. The log is controlled and accessed via the history command. The history facility uses the term event to mean an entry in its history log. The events are just commands, and they have an event ID that is their index in the log. You can also specify an event with a negative index that counts backwards from the end of the log. Event -1 is the previous event. Table 13-5 summarizes the Tcl history command. In the table, event defaults to -1.
In practice you will want to take advantage of the ability to abbreviate the history options and even the name of the history command itself. For the command, you need to type a unique prefix, ...
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