How can I see Bash history from more than one terminal session in Ubuntu? [duplicate]

Possible Duplicate:
Can history files be unified in bash?

I use Ubuntu Server 9.10 and I would like to be able to see my bash history for more than one terminal sessions. I.e. my last 200 commands or so, even if I have been logged out in between.

When I use the history I just see all commands from my actual terminal session. How can I see more command history from Bash? Is there any specific settings for bash that I should change from the default values in Ubuntu?

I don't have a ~/.bash_history file. But I have an ~/.bashrc with HISTCONTROL=$HISTCONTROL${HISTCONTROL+,}ignoredups and HISTCONTROL=ignoreboth

echo $HISTFILE
/home/sanoj/.bash_history
echo $HISTSIZE
500
echo $HISTFILESIZE
500
echo $HISTCONTROL
ignoreboth

UPDATE: I am now trying Ubuntu Server 10.10 in VirtualBox. If I just turn off VirtualBox without the shutdown command, then next time when I boot, the commands from the last session is not saved in the history file.

The commands are only saved if I shutdown the machine with the shutdown command. E.g. shutdown -P 0.

This must be the reason to my problem. So I have to figure out how to save the command-history more often. E.g. after each command.

Solution 1:

You can use

history -a

to immediately append the in-memory history to the history file. One terminal session can't see another's unless this is done or the other is exited.

You can use

history 200 | less

to see that number of entries.

In addition to HISTSIZE see the entry in the Bash man page concerning HISTFILESIZE.

Solution 2:

Once you log out the history gets appended to the file ~/.bash_history. Have a look in there.

By default it will remember your last 500 commands. If you want to save more set the variable HISTSIZE in ~/.bashrc.

I also do add ignoredups to HISTCONTROL (with HISTCONTROL=$HISTCONTROL:ignoredup). This makes duplicate consecutive commands to be save only once.

Have a look at man 1 bash for what else you can tune about the history.

Solution 3:

bash history is usually loaded when the shell begins running, and is saved when it is exited normally. You can use history -a and history -n to override this, but not automatically unless you abuse $PROMPT_COMMAND or something similar.