Python Ros1 melodic

sudo sh -c 'echo "deb http://packages.ros.org/ros/ubuntu $(lsb_release -sc) main" > /etc/apt/sources.list.d/ros-latest.list'

sudo apt-key adv --keyserver 'hkp://keyserver.ubuntu.com:80' --recv-key C1CF6E31E6BADE8868B172B4F42ED6FBAB17C654

sudo apt update

sudo apt install ros-melodic-desktop-full

sudo apt install python-rosdep python-rosinstall python-rosinstall-generator python-wstool build-essential

echo "source /opt/ros/melodic/setup.bash" >> ~/.bashrc
source ~/.bashrc

def start_ros_core():
    result_roscore = os.system('roscore')

ros1bag_core_process = multiprocessing.Process(target=start_ros_core)
ros1bag_core_process.start()

def sub_mutil():
    num = 0
    while True:
        my_msg = String()
        my_msg.data = f'{num}'
        pub_parking.publish(my_msg)
        time.sleep(1)
        print(f"发送消息:{num}")
        num+=1
sub_mutil()

def call_back_String(msg):
    print(f"吸取到消息: {msg.data}")
rospy.Subscriber('mystring',String, call_back_String)
rospy.spin()

import os
import sys
import time
import rospy
import multiprocessing
from std_msgs.msg import String
def start_ros_core():
    result_roscore = os.system('roscore')
ros1bag_core_process = multiprocessing.Process(target=start_ros_core)
ros1bag_core_process.start()
rospy.init_node("test_pub", anonymous=True)#初始化节点 名称：test
def sub_mutil():
    num = 0
    while True:
        my_msg = String()
        my_msg.data = f'{num}'
        pub_parking.publish(my_msg)
        time.sleep(1)
        print(f"发送消息:{num}")
        num+=1

pub_parking = rospy.Publisher('mystring', String, queue_size=10)
sub_mutil()