The ipython notebook has it’s own support for running shell commands. If you don’t need to capture with subprocess stuff you can just do cmd = ‘ls -l’ !{cmd} Output from commands executed with ! is automatically piped through the notebook.
It seems unusual to me that you use the patch decorator over the run_script function, since you don’t pass a mock argument there. How about this: from unittest import mock import subprocess def run_script(file_path): process = subprocess.Popen([“myscript”, -M, file_path], stdout=subprocess.PIPE) output, err = process.communicate() return process.returncode @mock.patch(“subprocess.Popen”) def test_run_script(self, mock_subproc_popen): process_mock = mock.Mock() attrs = … Read more
You’ve got two problems: 1 – subprocess.call() expects a list of arguments, not multiple arguments: #wrong subprocess.call(‘cp’, in, out) #right subprocess.call([‘cp’, in, out]) 2 – in is a python reserved keyword, change it to something like inp: #wrong subprocess.call([‘cp’, in, out]) #right subprocess.call([‘cp’, inp, out])
You can do this with subprocess, but it’s not trivial. If you look at the Frequently Used Arguments in the docs, you’ll see that you can pass PIPE as the stderr argument, which creates a new pipe, passes one side of the pipe to the child process, and makes the other side available to use … Read more
You should pass the arguments as a list (recommended): subprocess.Popen([“wc”, “-l”, “sorted_list.dat”], stdout=subprocess.PIPE) Otherwise, you need to pass shell=True if you want to use the whole “wc -l sorted_list.dat” string as a command (not recommended, can be a security hazard). subprocess.Popen(“wc -l sorted_list.dat”, shell=True, stdout=subprocess.PIPE) Read more about shell=True security issues here. In this case, … Read more
Use Popen.wait: process = subprocess.Popen([“your_cmd”]…) process.wait() Or check_output, check_call which all wait for the return code depending on what you want to do and the version of python. If you are using python >= 2.7 and you don’t care about the output just use check_call. You can also use call but that will not raise … Read more
The important thing about the optimization suggestion is to make sure that my_function() is only invoked in a subprocess. The deepcopy and del are irrelevant — once you create five million distinct integers in a process, holding onto all of them at the same time, it’s game over. Even if you stop referring to those … Read more
In Python 2, if a set of objects are linked together in a chain (reference cycle) and, at least, one object has a __del__ method, the garbage collector will not delete these objects. If you have a reference cycle, adding a __del__() method may just hide bugs (workaround bugs). According to your update #3, it … Read more
Yes, these md5sum processes will be started in parallel. Yes, the order of md5sums writes will be unpredictable. And generally it is considered a bad practice to share a single resource like file from many processes this way. Also your way of making p.wait() after the for loop will wait just for the last of … Read more
I think you misunderstand communicate… http://docs.python.org/library/subprocess.html#subprocess.Popen.communicate communicate sends a string to the other process and then waits on it to finish… (Like you said waits for the EOF listening to the stdout & stderror) What you should do instead is: proc.stdin.write(‘message’) # …figure out how long or why you need to wait… proc.stdin.write(‘message2’) (and if … Read more