copy the following codes and paste this code to file name bashrc which is locate in /home/username/ eg . /home/lazyboy/bashrc copy code from HERE or just copy following code ------------------------------------------------------------------------------------------------------------------------- # ~/.bashrc: executed by bash(1) for non-login shells. # see /usr/share/doc/bash/examples/startup-files (in the package bash-doc) # for examples # If not running interactively, don't do anything [ -z "$PS1" ] && return # don't put duplicate lines in the history. See bash(1) for more options # ... or force ignoredups and ignorespace HISTCONTROL=ignoredups:ignorespace # append to the history file, don't overwrite it shopt -s histappend # for setting history length see HISTSIZE and HISTFILESIZE in bash(1) HISTSIZE=1000 HISTFILESIZE=2000 # check the window size after each command and, if necessary, # update the values of LINES and COLUMNS. shopt -s