Python source file directory

Get the path of current file (script) in Python: __file__

In Python, you can use __file__ to get the path (location) of the current file, i.e., the currently running script file ( .py ). This is particularly useful when you need to read other files that are relative to the location of the current file.

In Python 3.8 and earlier, __file__ returns the path specified when executing the python (or python3 ) command. If you specify a relative path, a relative path is returned. If you specify an absolute path, an absolute path is returned.

From Python 3.9 onwards, however, __file__ will always return an absolute path, whether you used a relative or an absolute path, when executing the python command.

In the sample code in this article, suppose you work in the following directory. On Windows, you can check the current directory with the dir command instead of pwd .

pwd # /Users/mbp/Documents/my-project/python-snippets/notebook 

See the following article on how to get and change the current working directory in Python.

Note that __file__ is not available in Jupyter Notebook ( .ipynb ). No matter where you started the Jupyter Notebook, the current directory is where the .ipynb file is located. However, you can change the current directory by using os.chdir() in your code.

os.getcwd() and __file__

Create a Python script file ( file_path.py ) in the subdirectory ( data/src ).

import os print('getcwd: ', os.getcwd()) print('__file__: ', __file__) 

Execute this file with the python (or python3 ) command.

python3 data/src/file_path.py # getcwd: /Users/mbp/Documents/my-project/python-snippets/notebook # __file__: data/src/file_path.py 

You can get the absolute path of the current working directory with os.getcwd() and the path specified with the python3 command with __file__ .

In Python 3.8 and earlier, __file__ stores the path that was specified when executing the python (or python3 ) command. In the above example, a relative path is specified, so a relative path is returned. But, if an absolute path is specified, an absolute path is returned.

pwd # /Users/mbp/Documents/my-project/python-snippets/notebook python3 /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/file_path.py # getcwd: /Users/mbp/Documents/my-project/python-snippets/notebook # __file__: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/file_path.py 

In Python 3.9 and later, __file__ always stores an absolute path, regardless of whether the path specified with the python command is relative or absolute.

In the following examples, add code to the same script file ( file_path.py ) and execute it from the same directory as the above example, using Python 3.7.

Note that, if __file__ is an absolute path (which is always the case with Python 3.9 or later, and when specifying the absolute path in Python 3.8 or earlier), you can use the same code described below to read other files relative to the location of the current script file. The results of specifying the absolute path in Python 3.7 are shown at the end of this article.

Get the file and directory name of the current script file

You can use os.path.basename() and os.path.dirname() to get the file and directory name of the current script file.

import os print('basename: ', os.path.basename(__file__)) print('dirname: ', os.path.dirname(__file__)) 

# basename: file_path.py # dirname: data/src 

If you want to get only the directory name directly above the file, use os.path.basename(os.path.dirname(__file__)) .

Get the absolute path of the current script file

If __file__ stores the relative path, you can convert it to an absolute path using os.path.abspath() .

import os print('abspath: ', os.path.abspath(__file__)) print('abs dirname: ', os.path.dirname(os.path.abspath(__file__))) 

# abspath: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/file_path.py # abs dirname: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src 

Note that os.path.abspath() will simply return the same path if you give it an absolute path. So, even if __file__ is already an absolute path, using os.path.abspath(__file__) will not raise an error.

Read other files based on the location of the current script file

If you want to read other files that are located relative to the current script file, you can use os.path.join() to combine the directory path of the current file and the relative path of the file you want to read.

If a file is in the same directory as the script file, you can read it by just specifying its name.

import os print('[set target path 1]') target_path_1 = os.path.join(os.path.dirname(__file__), 'target_1.txt') print('target_path_1: ', target_path_1) print('read target file:') with open(target_path_1) as f: print(f.read()) 

# [set target path 1] # target_path_1: data/src/target_1.txt # read target file: # !! This is "target_1.txt" !! 

In a file path, ../ represents the parent directory. Although there is no problem as it is, os.path.normpath() normalizes the path and eliminates any unnecessary ../ segments.

print('[set target path 2]') target_path_2 = os.path.join(os.path.dirname(__file__), '../dst/target_2.txt') print('target_path_2: ', target_path_2) print('normalize : ', os.path.normpath(target_path_2)) print('read target file:') with open(target_path_2) as f: print(f.read()) 

# [set target path 2] # target_path_2: data/src/../dst/target_2.txt # normalize : data/dst/target_2.txt # read target file: # !! This is "target_2.txt" !! 

Please refer to the following article for more information on reading files:

Change the current directory to the directory of the current script file

You can use os.chdir() to change the current working directory to the directory where the current script file is located.

You can then use os.getcwd() to confirm the change.

import os print('[change directory]') os.chdir(os.path.dirname(os.path.abspath(__file__))) print('getcwd: ', os.getcwd()) 

# [change directory] # getcwd: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src 

If the current working directory is the same as the directory of the current file, you can use a relative path from the current file to read other files.

print('[set target path 1 (after chdir)]') target_path_1 = 'target_1.txt' print('target_path_1: ', target_path_1) print('read target file:') with open(target_path_1) as f: print(f.read()) print() print('[set target path 2 (after chdir)]') target_path_2 = '../dst/target_2.txt' print('target_path_2: ', target_path_2) print('read target file:') with open(target_path_2) as f: print(f.read()) 

# [set target path 1 (after chdir)] # target_path_1: target_1.txt # read target file: # !! This is "target_1.txt" !! # # [set target path 2 (after chdir)] # target_path_2: ../dst/target_2.txt # read target file: # !! This is "target_2.txt" !! 

Read the same file regardless of the current working directory

By using __file__ to obtain the path of the current script file, you can consistently read the same file, regardless of the current working directory.

As shown so far, there are two ways to do this:

• Join the __file__ directory and the relative path (from __file__ ) of the file you want to read with os.path.join() .
• Change the current working directory to the __file__ directory.

While it is simpler to change the current directory, any subsequent file reading or writing operations should take into account that the current directory has been changed.

The result of the examples so far is as follows.

pwd # /Users/mbp/Documents/my-project/python-snippets/notebook python3 data/src/file_path.py # getcwd: /Users/mbp/Documents/my-project/python-snippets/notebook # __file__: data/src/file_path.py # basename: file_path.py # dirname: data/src # abspath: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/file_path.py # abs dirname: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src # # [set target path 1] # target_path_1: data/src/target_1.txt # read target file: # !! This is "target_1.txt" !! # # [set target path 2] # target_path_2: data/src/../dst/target_2.txt # normalize : data/dst/target_2.txt # read target file: # !! This is "target_2.txt" !! # # [change directory] # getcwd: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src # # [set target path 1 (after chdir)] # target_path_1: target_1.txt # read target file: # !! This is "target_1.txt" !! # # [set target path 2 (after chdir)] # target_path_2: ../dst/target_2.txt # read target file: # !! This is "target_2.txt" !! 

The results when specifying the absolute path with the python3 command are as follows. As you can see, you can read the same file:

pwd # /Users/mbp/Documents/my-project/python-snippets/notebook python3 /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/file_path.py # getcwd: /Users/mbp/Documents/my-project/python-snippets/notebook # __file__: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/file_path.py # basename: file_path.py # dirname: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src # abspath: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/file_path.py # abs dirname: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src # # [set target path 1] # target_path_1: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/target_1.txt # read target file: # !! This is "target_1.txt" !! # # [set target path 2] # target_path_2: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/../dst/target_2.txt # normalize : /Users/mbp/Documents/my-project/python-snippets/notebook/data/dst/target_2.txt # read target file: # !! This is "target_2.txt" !! # # [change directory] # getcwd: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src # # [set target path 1 (after chdir)] # target_path_1: target_1.txt # read target file: # !! This is "target_1.txt" !! # # [set target path 2 (after chdir)] # target_path_2: ../dst/target_2.txt # read target file: # !! This is "target_2.txt" !! 

Change the current directory in the terminal and execute the same script file. You can see that the same file is read, even though the current directory is different:

cd data/src pwd # /Users/mbp/Documents/my-project/python-snippets/notebook/data/src python3 file_path.py # getcwd: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src # __file__: file_path.py # basename: file_path.py # dirname: # abspath: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src/file_path.py # abs dirname: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src # # [set target path 1] # target_path_1: target_1.txt # read target file: # !! This is "target_1.txt" !! # # [set target path 2] # target_path_2: ../dst/target_2.txt # normalize : ../dst/target_2.txt # read target file: # !! This is "target_2.txt" !! # # [change directory] # getcwd: /Users/mbp/Documents/my-project/python-snippets/notebook/data/src # # [set target path 1 (after chdir)] # target_path_1: target_1.txt # read target file: # !! This is "target_1.txt" !! # # [set target path 2 (after chdir)] # target_path_2: ../dst/target_2.txt # read target file: # !! This is "target_2.txt" !! 

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