subprocess

问题 I have a program written in python and used git command in it.. For some reason I don't want to use git-python or others instead of subprocess. But I'm currently stuck in getting git clone output. I've tried some code snippet. Some works fine with commands like ping 8.8.8.8 , but not the git clone . for example using thread def log_worker(stdout): while True: last = non_block_read(stdout).strip() if last != "": print(last) def non_block_read(output): fd = output.fileno() fl = fcntl.fcntl(fd,

问题 Take the shell command "cat file.txt" as an example. With Popen, this could be run with import subprocess task = subprocess.Popen("cat file.txt", shell=True, stdout=subprocess.PIPE) data = task.stdout.read() With check_output, one could run import subprocess command=r"""cat file.log""" output=subprocess.check_output(command, shell=True) These appears to be equivalent. What is the difference with regards to how these two commands would be used? 回答1: Popen is the class that defines an object

问题 Take the shell command "cat file.txt" as an example. With Popen, this could be run with import subprocess task = subprocess.Popen("cat file.txt", shell=True, stdout=subprocess.PIPE) data = task.stdout.read() With check_output, one could run import subprocess command=r"""cat file.log""" output=subprocess.check_output(command, shell=True) These appears to be equivalent. What is the difference with regards to how these two commands would be used? 回答1: Popen is the class that defines an object

问题 I am using the subprocess module to run a find & grep command with two different variables. I have a syntax error but I just don't see it. With one variable, it runs just fine: path = "src" path_f = "TC" subprocess.Popen('find /dir1/tag/common/dir2/dir3 /dir1/tag/common/dir2/dir3/dir4/ -iname "%s"'%path, shell=True) Two variables: subprocess.Popen('find /dir1/tag/common/dir2/dir3 /dir1/tag/common/dir2/dir3/dir4/ -iname "%s"* | grep "%s" > fileList.txt'%path, %path_f, shell=True) Can someone

问题 Example: #!/bin/bash function my_test(){ echo this is a test $1 } my_test 1 python -c "from subprocess import check_output; print(check_output('my_test 2', shell=True))" output: this is a test 1 /bin/sh: my_test: command not found Traceback (most recent call last): File "<string>", line 1, in <module> File "/usr/lib/python3.5/subprocess.py", line 629, in check_output **kwargs).stdout File "/usr/lib/python3.5/subprocess.py", line 711, in run output=stdout, stderr=stderr) subprocess

问题 code in fork_child.py from subprocess import Popen child = Popen(["ping", "google.com"], stdout=subprocess.PIPE,stderr=subprocess.PIPE) out, err = child.communicate() I run it from a terminal window as - $python fork_child.py From another terminal window if I get the PID of fork_child.py and kill it with SIGTERM, "ping" doesn't get killed. How do I make sure that ping too gets killed when fork_child receives a SIGTERM ? 回答1: Children don't automatically die when the parent process is killed.

问题 code in fork_child.py from subprocess import Popen child = Popen(["ping", "google.com"], stdout=subprocess.PIPE,stderr=subprocess.PIPE) out, err = child.communicate() I run it from a terminal window as - $python fork_child.py From another terminal window if I get the PID of fork_child.py and kill it with SIGTERM, "ping" doesn't get killed. How do I make sure that ping too gets killed when fork_child receives a SIGTERM ? 回答1: Children don't automatically die when the parent process is killed.

问题 I am trying to run multiple instances of a console-based game (dungeon crawl stone soup -- for research purposes naturally) using a multiprocessing pool to evaluate each run. In the past when I've used a pool to evaluate similar code (genetic algorithms), I've used subprocess.call to split off each process. However, with dcss being quite interactive having a shared subshell seems to be problematic. I have the code I normally use for this kind of thing, with crawl replacing other applications

问题 Consider this code, where a subprocess.Popen is spawned. I'd like writes to the subprocess' stdout and stderr to go to my custom file-object's .write() method, however this isn't the case. import subprocess class Printer: def __init__(self): pass def write(self, chunk): print('Writing:', chunk) def fileno(self): return 0 def close(self): return proc = subprocess.Popen(['bash', '-c', 'echo Testing'], stdout=Printer(), stderr=subprocess.STDOUT) proc.wait() Why is the .write() method not used,

问题 Consider this code, where a subprocess.Popen is spawned. I'd like writes to the subprocess' stdout and stderr to go to my custom file-object's .write() method, however this isn't the case. import subprocess class Printer: def __init__(self): pass def write(self, chunk): print('Writing:', chunk) def fileno(self): return 0 def close(self): return proc = subprocess.Popen(['bash', '-c', 'echo Testing'], stdout=Printer(), stderr=subprocess.STDOUT) proc.wait() Why is the .write() method not used,