How to Set Working Directory for Subprocesses in Python

In Python, the subprocess.Popen() function allows you to execute commands within a subprocess. One common requirement is to specify the working directory for the subprocess.

Question:

How can you set the working directory for a subprocess using subprocess.Popen()?

Answer:

To specify the working directory, use the cwd argument of subprocess.Popen(). The cwd argument expects an absolute path to the desired working directory.

Example:

Suppose your Python script is located at C:\programs\python and you want to run C:\mytool\tool.exe in the directory D:\test\local. You can use the following syntax:

import os

# Get the current Python script directory
cwd = os.path.dirname(os.path.realpath(__file__))

# Execute "C:\mytool\tool.exe" with the specified working directory
subprocess.Popen(r'C:\mytool\tool.exe', cwd=r'D:\test\local')

Note:

• Ensure to use raw strings (prefixed with r) to avoid interpreting backslashes as escape sequences.
• If you wish to use the current Python script directory as the working directory, use os.path.dirname(os.path.realpath(__file__)).