Member Avatar for Surge591

Hello,

I would like to know how I can call a program ('example.exe') which runs as a batch process in a new command prompt and control the inputs and outputs from within a python script. I have tried the following code:

import subprocess

p = subprocessPopen('example.exe', shell=True, stdin=PIPE, stdout=PIPE, stderr=STDOUT)
#this line opens the example code in a new command prompt
p.stdin.write('hello')
#i now need to send input into the example code.

But this only ends up hanging up without any information being sent into the command prompt. How can I control the data being sent into a command prompt using python.

Thanks in advance,

Surge

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  • Latest Post Latest Post by vegaseat
Member Avatar for vegaseat

This is an example on how to run Python code externally ...

# pipe the output of calendar.prmonth() to a string: import subprocess code_str = \ """ import calendar calendar.prmonth(2006, 3) """ # save the code filename = "mar2006.py" fout = open(filename, "w") fout.write(code_str) fout.close() # execute the .py code and pipe the result to a string test = "python " + filename process = subprocess.Popen(test, shell=True, stdout=subprocess.PIPE) # important, wait for external program to finish process.wait() print process.returncode # 0 = success, optional check # read the result to a string month_str = process.stdout.read() print month_str

More general ...

import subprocess # put in the corresponding strings for # "mycmd" --> external program name # "myarg" --> arg for external program # several args can be in the list ["mycmd", "myarg1", "myarg2"] # might need to change bufsize p = subprocess.Popen(["mycmd", "myarg"], bufsize=2048, shell=True, stdin=subprocess.PIPE, stdout=subprocess.PIPE, close_fds=True) # write a command to the external program p.stdin.write("some command string here") # allow external program to work p.wait() # read the result to a string result_str = p.stdout.read()
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