Ubuntu – How to view the `.bash_history` file via command line

bashcommand linehistory

I want to view the contents of my .bash_history file but don't know how to get there via the command line.

Best Answer

If you want to access the actual file itself, just use your favorite text editor (I use emacs but you can use pluma of gedit or vimor whatever):

emacs ~/.bash_history

That is the default location if your history file. If you don't find anything there, you may have changed the history file's name. This is stored in the $HISTFILE variable, so print it out to check its current value:

echo $HISTFILE

If, instead of the file, you just want to see your history, you can run history as @minerz029 suggested. The history command with no options just prints the contents of your $HISTFILE followed by the commands executed in the current shell that have not yet been written to that file, with line numbers.

Related Solutions

Ubuntu – How to avoid duplicate entries in .bash_history

From the bash man page:

HISTCONTROL

A colon-separated list of values controlling how commands are saved on the history list. If the list of values includes ignorespace, lines which begin with a space character are not saved in the history list. A value of ignoredups causes lines matching the previous history entry to not be saved. A value of ignoreboth is shorthand for ignorespace and ignoredups. A value of erasedups causes all previous lines matching the current line to be removed from the history list before that line is saved. Any value not in the above list is ignored. If HISTCONTROL is unset, or does not include a valid value, all lines read by the shell parser are saved on the history list, subject to the value of HISTIGNORE. The second and subsequent lines of a multi-line compound command are not tested, and are added to the history regardless of the value of HISTCONTROL.

So put the following line in your ~/.bashrc:

export HISTCONTROL=ignoreboth:erasedups

Ubuntu – How to install a .deb file via the command line

Packages are manually installed via the dpkg command (Debian Package Management System). dpkg is the backend to commands like apt-get and aptitude, which in turn are the backend for GUI install apps like the Software Center and Synaptic.

Something along the lines of:

dpkg --> apt-get, aptitude --> Synaptic, Software Center

But of course the easiest ways to install a package would be, first, the GUI apps (Synaptic, Software Center, etc..), followed by the terminal commands apt-get and aptitude that add a very nice user friendly approach to the backend dpkg, including but not limited to packaged dependencies, control over what is installed, needs update, not installed, broken packages, etc.. Lastly the dpkg command which is the base for all of them.

Since dpkg is the base, you can use it to install packaged directly from the command line.

Install a package

sudo dpkg -i DEB_PACKAGE

For example if the package file is called askubuntu_2.0.deb then you should do sudo dpkg -i askubuntu_2.0.deb. If dpkg reports an error due to dependency problems, you can run sudo apt-get install -f to download the missing dependencies and configure everything. If that reports an error, you'll have to sort out the dependencies yourself by following for example How do I resolve unmet dependencies after adding a PPA?.

Remove a package

sudo dpkg -r PACKAGE_NAME

For example if the package is called askubuntu then you should do sudo dpkg -r askubuntu.

Reconfigure an existing package

sudo dpkg-reconfigure PACKAGE_NAME

This is useful when you need to reconfigure something related to said package. Some useful examples it the keyboard-configuration when you want to enable the Ctrl+Alt+Backspace in order to reset the X server, so you would the following:

sudo dpkg-reconfigure keyboard-configuration

Another great one is when you need to set the Timezone for a server or your local testing computer, so you use use the tzdata package:

sudo dpkg-reconfigure tzdata