# 
## Method overview
This **`os.ctermid()` method**  fetches the filename corresponding to the controlling terminal (i.e., the #key# POSIX: Portable Operating System Interface Family #key# terminal) of the process.
> The controlling terminal supervises a set of threads or processes grouped as a session.


## Syntax
---
```python
os.ctermid()
```
---

It does not take any argument value, nor does it return any.
## Explanation
Let's elaborate on this function with a code explanation:

# for UNIX based systems
# demo code about ctermid()
import os
# printing about filename controlling terminal
print("Filename parallel to the controlling terminal:")
print(os.ctermid())

* **Line 3:** We import the `os` module in the program.
* **Line 5:** We print the function call.
* **Line 6:** We call `os.ctermid()` to get the filename parallel to the controlling terminal.

What is the os.ctermid() method in Python?

Retrieves the filename for the process's controlling terminal, without requiring or returning arguments.