whoami Command in Linux (Find Logged In User)

whoami is an basic Unix/Linux command used to find username associated with current effective user id. This is generally used to identify the current logged in user in a shell. This command is also useful in shell scripts to identify the user id from which the script is running.

Syntax:

whoami [OPTION]...

whoami Command in Linux

Simply type the ‘whoami’ on command prompt to find logged in user in current shell.

whoami 

root

The above output shows that you are logged in with user ‘root’ in current shell. The same details can be find with id -un command in Linux.

id -un 

root

Let’s write a small bash shell script and check if script is running as root user or not. This is very useful to warn user that the script is running as root user.

Difference Between whoami and who am i Command

Both the commands whoami and who am i are used to get logged in username in Linux system. The username is defined in passwd file associate with effective user id.

When a user login as root on the network, then both whoami and who am i commands will return root.

whoami 

Output:>  root 

who am i 

Output:>  root     pts/14       2020-12-21 23:13 (150.242.65.112) 

But, when you logged in as another user (eg: rahul) and switched to root user (su – root). The whoami will show root but who am i will show the originally logged in user ‘rahul’.

whoami 

Output:>  root 

who am i 

Output:>  rahul     pts/14       2020-12-21 23:16 (150.242.65.112) 

Conclusion

In this tutorial, you have learn about Linux whoami command as well as difference with “who am i” command.