


Executing Programs and System Commands in Python
In Python, you may need to interact with external programs or issue system commands from within your code. To accomplish this, Python provides several mechanisms, including subprocess.run and os.system.
subprocess.run
subprocess.run is a popular and versatile method for executing programs and commands. It provides a simple and straightforward interface. Here's how to use it:
import subprocess subprocess.run(["ls", "-l"])
This code will execute the "ls -l" command, just as if you had typed it in a shell or command prompt.
os.system
os.system is another option, but it is generally discouraged due to security concerns. It offers less control over the execution and is susceptible to certain security vulnerabilities.
subprocess.call
For Python 3.4 and earlier, subprocess.call should be used instead of subprocess.run. It serves the same purpose as subprocess.run, but with slightly different syntax.
subprocess.call(["ls", "-l"])
Advantages of subprocess.run
Compared to os.system, subprocess.run offers several advantages:
- Security: subprocess.run provides more control over the execution environment, making it less vulnerable to security issues.
- Flexibility: subprocess.run allows you to capture the output, the error stream, and the exit code, providing more information about the executed program.
- Cross-platform: subprocess.run works consistently across different operating systems.
Conclusion
subprocess.run and subprocess.call are the preferred options for executing programs or system commands in Python. They offer a combination of security, flexibility, and cross-platform compatibility.
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