UNIX Command History

One of the great things about Mac OSX is that it is based on Unix. One of the greatest thing in Unix is its terminal. However in my new mac I see that I need to re-type every command even I have just typed before… Usually you expect your command to be stored in .bash_history and when you hit upper arrow key you should be able to see the previous commands you typed. That was not the case with this Mac.

I checked/Users/ismail directory for .bash_history file. There was none. I created with touch command.

touch .bash_history
I tried with no help… Next I see there was no .bash_profile file neither. I created that with touch too:
touch .bash_profile

I then edited the .bash_profile :
HISTFILESIZE=5000 HISTSIZE=5000 HISTFILE=/Users/ismailg/.bash_history

HISTFILESIZE
The maximum number of lines contained in the history file. When this variable is assigned a value, the history file is trun-
cated, if necessary, to contain no more than that number of lines.

HISTSIZE
The number of commands to remember in the command history

Now you should be able to use arrow keys to get previous commands. In the next blog post we will discuss how to make Unix systems not records your commands even if you are a regular user in box and how to control attackers to delete .bash_history

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