Start Jack

[SrMouraSilva]

Useful for real mod-devices test

---

No library was found to start or manage a jack daemon.
I believe a new library should be implemented for this.

--

Async io - https://medium.freecodecamp.com/a-guide-to-asynchronous-programming-in-python-with-asyncio-232e2afa44f6

[SrMouraSilva]

Subprocess Asyncio https://docs.python.org/3/library/asyncio-subprocess.html
code examples: http://www.programcreek.com/python/example/82526/asyncio.create_subprocess_exec

import asyncio
import signal
from subprocess import PIPE

@asyncio.coroutine
def ls(loop):
    arguments = ['ls', '-la']
    proc = yield from asyncio.create_subprocess_exec(*arguments, stdout=PIPE)

    while True:
        line = yield from proc.stdout.readline()
        if not line:
            break
        print("ls>>", line.decode('ascii').rstrip())

    print('CLOSED')
    try:
        proc.send_signal(signal.SIGINT)
    except ProcessLookupError:
        pass

@asyncio.coroutine
def call_process(loop, arguments, function):
    proc = yield from asyncio.create_subprocess_exec(*arguments, stdout=PIPE)

    while True:
        line = yield from proc.stdout.readline()
        if not line:
            break
        function(line.decode('ascii').rstrip())

    try:
        proc.send_signal(signal.SIGINT)
    except ProcessLookupError:
        pass

def inspect(line):
    print('> ', line)

loop = asyncio.get_event_loop()
# Blocking call which returns when the hello_world() coroutine is done
loop.run_until_complete(call_process(loop, ['jackd', '-d', 'alsa'], inspect))
#loop.close()

try:
    loop.run_forever()
finally:
    loop.close()

[SrMouraSilva]

import subprocess

'''
def execute(cmd):
    popen = subprocess.Popen(cmd, stdout=subprocess.PIPE, universal_newlines=True)

    for stdout_line in popen.stdout:
        print(stdout_line)
        yield stdout_line

    popen.stdout.close()
    return_code = popen.wait()
    if return_code:
        raise subprocess.CalledProcessError(return_code, cmd)
'''

# Example
#command = 'jackd -R -P70 -t2000 -dalsa -dhw:0 -p256 -n3 -r44100 -s'.split()
command = 'mod-host'.split()
#for path in execute(command):
#    print(path, end="")

'''
with subprocess.Popen(command, stdout=subprocess.PIPE, bufsize=1, universal_newlines=True) as p:
    try:
        for line in p.stdout:
            print('AAA', line, end='') # process line here
    except:
        print("cadê")
        p.stdout.close()
        return_code = popen.wait()
        if return_code:
            raise subprocess.CalledProcessError(return_code, cmd)
'''

'''
with subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE) as p:
    for line in p.stderr:
        print('Error:', line)
'''

'''
with subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE) as p:
    for output, error in p.communicate():
        print('output:', output)
        print('error:', error)
'''

with subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE) as p:
#    for line in p.stderr:
    for line in p.stdout:
        print('Error:', line)