Keep subprocess alive to run other commands

Question

In a python3 script I need to call other commands in a particular environment (python2 among other stuff). For this I need to source a dotshrc file in a particular directory, and then stay in that directory to run other commands.

It looks like this:

proc = subprocess.Popen("source dotshrc", shell=True, cwd="/my/dir")

# do some stuff

if foo:
  proc.*run*(cmd = "myCmd1")

# do some stuff

proc.*run*(cmd = "myCmd2")

I saw multiple threads talking about running multiple commands on python sub-processes.

This one, who run all commands in a row, so I can not do my own stuff between commands runs.
This other one who looks promising, but I can't achieve to make it works. Here is a little test I wrote:

#!/usr/bin/env python3
from subprocess import Popen, PIPE
import os

my_env = os.environ.copy()
my_env["PATH"] = "/foo/:" + my_env["PATH"]

proc = Popen("echo $PATH", env=my_env, shell=True, stdin=PIPE, stdout=PIPE)
if proc.poll() is not None:
    print("Exited 1")
    exit()

print(repr(proc.stdout.readline()))

if proc.poll() is not None:
    print("Exited 2")
    exit()

print(proc)

if proc.poll() is not None:
    print("Exited 3")
    exit()

proc.stdin.write(b'echo')

if proc.poll() is not None:
    print("Exited 4")
    exit()

print(repr(proc.stdout.readline()))

if proc.poll() is not None:
    print("Exited 5")
    exit()

proc.stdin.write(b'ls')

if proc.poll() is not None:
    print("Exited 6")
    exit()

print(repr(proc.stdout.readline()))

if proc.poll() is not None:
    print("Exited 7")
    exit()

Most of the time it exit at Exit 2 or Exit 3

Keep subprocess alive to run other commands

0 Answers0