Python os.getlogin() Method

1. Syntax of Python os.getlogin() Method
2. Example 1: Use the os.getlogin() Method in Python
3. Example 2: Fix the OSError: Inappropriate ioctl for device in Python

The Python programming language offers a module os that contains various methods and system calls to interact with the operating system. One such method is the getlogin() method.

This method returns the name of the currently logged-in user.

Syntax of Python os.getlogin() Method

os.getlogin()

Parameters

This method doesn’t accept any parameters.

Return

The getlogin() method returns the logged-in user’s name.

Example 1: Use the os.getlogin() Method in Python

import os

user = os.getlogin()
print(user)

Output:

vaibhav

The output shows the name of the currently logged-in user.

Example 2: Fix the OSError: Inappropriate ioctl for device in Python

A controlling terminal refers to the one that assigns a user the power to control the execution of tasks or jobs during the active session. Without such a terminal, the getlogin() method throws the following error.

OSError: [Errno 25] Inappropriate ioctl for device

We can use the getpass.getuser() method to solve this problem. The getpass module is an in-built Python library that helps read user inputs as passwords.

This module has a method getuser() that returns the logged-in user. This method checks environment variables to resolve the logged-in user’s name, namely, LOGNAME, USER, LNAME, and USERNAME, in this specific order returns the first non-empty string value.

Generally, environment variables in systems are used to store sensitive details about applications for security purposes. Hence, they become an ideal spot to search for information.

If this method fails to resolve a name from these environment variables, it looks up to the pwd module. The pwd stands for Password Database.

Note that this module is only available in UNIX-based systems. The pwd module grants access to user details and its password database.

One of its methods, getpwuid(), helps retrieve the password database for a given numeric user ID. The user ID can be retrieved using the os.getuid() method.

Putting all this together, we get pwd.getpwuid(os.getuid())[0] that helps reveal logged in user’s name.

Refer to the following Python code for the solution.

import getpass

print(getpass.getuser())

Output:

vaibhav