051. history commands and execution time

Because Linux's default history record only saves the command content, there is no specific time, I can only find the user's logon and exit time to give them a time range.

Therefore, it is necessary to optimize the record function of history commands. The recommended parameters are as follows:

Edit/etc/profile and add the following configuration information:

	# Set the file size for saving History commands
	Export HISTFILESIZE = 1000000000
	# Number of historical commands saved
	Export HISTSIZE = 1000000
	# Real-Time History commands. By default, records are recorded only after the user exits, which easily overwrites multiple users.
	Export PROMPT_COMMAND = "history-"
	# Record the execution time of each historical command
	Export HISTTIMEFORMAT = "% Y-% m-% d _ % H: % M: % S" Or: export HISTTIMEFORMAT = "% F % T 'whoam '"

Make changes take effect immediately:

# Source/etc/bashrc