- 1 year ago
python subprocess provide input and read output multiple times [windows]
To interact with a subprocess multiple times by providing input and reading output, you can use the subprocess
module in Python. Here's an example of how to achieve this on Windows:
pythonimport subprocess
def run_subprocess(command, input_data):
# Create the subprocess and set the `stdin`, `stdout`, and `stderr` to pipes
process = subprocess.Popen(command, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
# Provide input to the subprocess
process.stdin.write(input_data)
process.stdin.flush()
# Read the output from the subprocess
output, errors = process.communicate()
# Return the output and errors
return output, errors
# Example usage:
command = 'python -c "print(input())"'
input_data = 'Hello, subprocess!\n'
# Run the subprocess multiple times
for _ in range(3):
output, errors = run_subprocess(command, input_data)
print("Output:", output.strip())
print("Errors:", errors.strip())
In this example, the run_subprocess
function is responsible for creating the subprocess, providing input to it, and reading the output. The text=True
parameter is used to ensure that the output is returned as a string instead of bytes.
You can replace the command
variable with the path to your executable and input_data
variable with the input you want to provide to the subprocess. The loop in the example demonstrates how you can repeatedly interact with the subprocess.
Note that the communicate
method will wait for the subprocess to finish before returning the output. If you want to interact with the subprocess asynchronously, you'll need to use other methods, such as poll
and stdout.readline
.