Lesson 1.13: Defining Command Alias

Defining Command Alias Temporarily

 
[sanjeeb@assignmentserver ~]$ alias
alias cls='clear'
alias egrep='egrep --color=auto'
alias fgrep='fgrep --color=auto'
alias grep='grep --color=auto'
 
[sanjeeb@assignmentserver ~]$ alias safagara='clear'

Defining Command Alias Permanently

CASE 1 : User Specific Alias

 
[sanjeeb@assignmentserver ~]$ # View hidden files 
[sanjeeb@assignmentserver ~]$ ls -a 
.              .bash_profile  Desktop    image.png  .mozilla  Script     test
..             .bashrc        Documents  .lesshst   Music     Scripts    Videos
.bash_history  .cache         Downloads  .local     Pictures  .ssh       .viminfo
.bash_logout   .config        folder     Marketing  Public    Templates
 
[sanjeeb@assignmentserver ~]$ # Open .bashrc and then add the specific line
[sanjeeb@assignmentserver ~]$ vi .bashrc
alias safagara='clear'
 
[sanjeeb@assignmentserver ~]$ # Refresh .bashrc
[sanjeeb@assignmentserver ~]$ . .bashrc
# OR
[sanjeeb@assignmentserver ~]$ source .bashrc

CASE 2 : System Wide Alias

 
# Switch to root user
[root@assignmentserver ~]# whoami 
root
 
# Find the .bashrc file in the hidden file of the root directory 
[root@assignmentserver ~]# ls -a
.                backup2        .cache   Desktop    .local    .ssh       .viminfo
..               .bash_history  .config  Documents  Music     .tcshrc    .xauthtK6NH4
allerr           .bash_logout   .cshrc   Downloads  Pictures  Templates
allout           .bash_profile  data1    full_out   Public    userinfo
anaconda-ks.cfg  .bashrc        data2    .lesshst   scr       Videos
 
# Edit the .bashrc file and add alias command
[root@assignmentserver ~]# vim .bashrc 
alias safagara='clear'
 
# Refresh the .bashrc
[root@assignmentserver ~]# source .bashrc
 
# View the alias
[root@assignmentserver ~]# alias
alias cp='cp -i'
alias egrep='egrep --color=auto'
alias fgrep='fgrep --color=auto'
alias grep='grep --color=auto'
alias l.='ls -d .* --color=auto'
alias ll='ls -l --color=auto'
alias ls='ls --color=auto'
alias mv='mv -i'
alias rm='rm -i'
alias safagara='clear'
alias xzegrep='xzegrep --color=auto'
alias xzfgrep='xzfgrep --color=auto'
alias xzgrep='xzgrep --color=auto'
alias zegrep='zegrep --color=auto'
alias zfgrep='zfgrep --color=auto'
alias zgrep='zgrep --color=auto'
 
# Check if the command is working
[root@assignmentserver ~]# safagara