history: Event Designators
1.1.1 Event Designators
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An event designator is a reference to a command line entry in the
history list. Unless the reference is absolute, events are relative to
the current position in the history list.
'!'
Start a history substitution, except when followed by a space, tab,
the end of the line, or '='.
'!N'
Refer to command line N.
'!-N'
Refer to the command N lines back.
'!!'
Refer to the previous command. This is a synonym for '!-1'.
'!STRING'
Refer to the most recent command preceding the current position in
the history list starting with STRING.
'!?STRING[?]'
Refer to the most recent command preceding the current position in
the history list containing STRING. The trailing '?' may be
omitted if the STRING is followed immediately by a newline.
'^STRING1^STRING2^'
Quick Substitution. Repeat the last command, replacing STRING1
with STRING2. Equivalent to '!!:s/STRING1/STRING2/'.
'!#'
The entire command line typed so far.