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LuukS

Member

Registered: 2019-01-02

Posts: 1

shell command from subprocess.Popen, two instances of VLC

I am trying to control two instances of VLC from a python script. To communicate I use unix sockets and netcat.
In the terminal it works well like this:

Initialize both instances:

vlc -I oldrc --rc-unix=/home/user/Documents/Sockets/socket1.sock
vlc -I oldrc --rc-unix=/home/user/Documents/Sockets/socket2.sock

Enqueue and play with:

echo play | nc -U /home/user/Documents/Sockets/socket1.sock
echo enqueue /home/user/Documents/DualscreenVLC/videos/MVI_2534.MP4 | nc -U /home/user/Documents/Sockets/socket1.sock

But when I translate it in Python to subprocess.Popen calls the script stops working.
On my mac osx system it does work... is there something wrong with the way I migrated it?

import subprocess
import time

Socket1Location = "/Users/user/socket1.sock"
Socket2Location = "/Users/user/socket2.sock"
video1 = "/Users/user/Documents/Scripts/DualscreenVLC/videos/video01.mp4"
video2 = "/Users/user/Documents/Scripts/DualscreenVLC/videos/video02.mp4"
duration = 30

def RunVLCCommand1(cmd):
	p = subprocess.Popen("echo " + cmd + " | nc -U " + Socket1Location, shell = True, stdout = subprocess.PIPE)
	errcode = p.wait()
	retval = p.stdout.read()
	print "returning: " + retval
	return retval 
	
def RunVLCCommand2(cmd):
	p = subprocess.Popen("echo " + cmd + " | nc -U " + Socket2Location, shell = True, stdout = subprocess.PIPE)
	errcode = p.wait()
	retval = p.stdout.read()
	print "returning: " + retval
	return retval 

print("BEFORE SUBPROCESS 1 : " + RunVLCCommand1("status"))
print("BEFORE SUBPROCESS 2 : " + RunVLCCommand2("status"))

subprocess.Popen(["/Applications/VLC.app/Contents/MacOS/VLC","--rc-unix=/Users/user/socket1.sock"])
subprocess.Popen(["/Applications/VLC.app/Contents/MacOS/VLC","--rc-unix=/Users/user/socket2.sock"])

#wait while initialising
while RunVLCCommand1("status") == "" or RunVLCCommand2("status") == "":
	print "Sockets loading..."
	time.sleep(1)
	if RunVLCCommand1("status") != False and RunVLCCommand2("status") != False:
		print "Sockets loaded"

#load videos
RunVLCCommand1("enqueue " + video1)
RunVLCCommand2("enqueue " + video2)
time.sleep(2)
RunVLCCommand1("play")
RunVLCCommand1("pause")
RunVLCCommand2("play")
RunVLCCommand2("pause")

#videos ready, wait for user input
raw_input("Press enter to start video...")
RunVLCCommand1("pause")
RunVLCCommand2("pause")