Readme and linter changes

Author: dieriver

README.md

@@ -24,13 +24,11 @@ Then you can install Python 3.12 and the Python development package:
 ```shell
 sudo apt-get install python3.12-full python3.12-dev
 ```
-
 Additionally, you will need the `build-essential` package, to install tools used when building some SimulaQron dependencies:
 
 ```shell
 sudo apt-get install build-essential cmake vim linux-headers-generic
 ```
-
 After this point, you should have all the required dependencies.
 
 
@@ -64,13 +62,11 @@ by using the Makefile:
 ```shell
 make install
 ```
-
 Additionally, you can install SimulaQron with extra dependencies:
 ```shell
 make install-optional
 ```
 
-
 Finally, if you would like to contribute to the development of SimulaQron, please install the development dependencies:
 ```shell
 make install-development
@@ -94,7 +90,7 @@ In Windows, SimulaQron can be installed in two similar ways:
 
 #### Native installation
 
-SimulaQron has also been tested working on macOS Tahoe (26.5) on an M3 pro CPU.
+SimulaQron has also been tested working on macOS Tahoe (26.5) on an M3 Pro CPU.
 
 Before proceeding with the SimulaQron install, you need to install python 3.12, which is available from the
 [Homebrew package manager](https://brew.sh/). Once that homebrew has been installed, you can install Python
@@ -104,8 +100,15 @@ Before proceeding with the SimulaQron install, you need to install python 3.12,
 brew install python@3.12
 ```
 
-After this, you can follow the instructions to install SimulaQron either [from PyPI](#installing-from-pypi)
-or directly [from this repository](#installing-from-this-repository).
+Additionally, to install the optional dependencies, you will need to install *XCode COmmand Line Tools*. To do
+so, run the following command in a terminal:
+
+```shell
+xcode-select --install
+```
+
+And follow the instructions on the screen. After this, you can follow the instructions to install SimulaQron
+either [from PyPI](#installing-from-pypi) or directly [from this repository](#installing-from-this-repository).
 
 
 #### Using the provided virtual machines

simulaqron/cli.py

@@ -25,6 +25,17 @@
     Path.mkdir(PID_FOLDER)
 
 
+# The following two classes (SimulaQronDaemon and RunningSimulaQronDaemon) are 2 classes that
+# implement the simulaqron daemon process.
+# The former class models a daemon process used to launch the backend processes
+# (1 Vnode and 1 QNodeOS process per node starting), and then it simply goes to sleep.
+# The latter class is used when invoking "simulaqron stop" to "reattach" to the launching
+# daemon process, and kill all the backend processes.
+# Both of the mentioned classes rely on the python "daemons" package, **which is designed
+# to run on Unix platforms** (Linux/macOS). Implementing a similar behavior in Windows
+# will require a heavy reimplementation of these 2 classes.
+
+
 class RunningSimulaQronDaemon(run.RunDaemon):
     """
     SimulaQronDaemon class used to represent SimulaQron daemons that are already running.

simulaqron/network.py

@@ -28,18 +28,24 @@
 # SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 import random
+import sys
 import time
 from timeit import default_timer as timer
 from typing import List, Dict
 
 import networkx as nx
-from multiprocess.context import ForkProcess as Process
+
+if sys.platform == "win32":
+    # Windows does not support "fork", so new processes need to be created with
+    # the spawn method.
+    from multiprocess.context import SpawnProcess as Process
+else:
+    from multiprocess.context import ForkProcess as Process
 import logging
 from pathlib import Path
 
 from simulaqron.settings import network_config
 from simulaqron.settings.network_config import NodeConfig
-from simulaqron.settings import simulaqron_settings
 from simulaqron.start import start_vnode, start_qnodeos
 # WARNING - this import *needs* to be after importing start_vnode and start_qnodeos
 # Otherwise the code that patches some netqasm internal definitions will not work correctly!

simulaqron/start/start_qnodeos.py

@@ -5,7 +5,7 @@
 from timeit import default_timer as timer
 
 import logging
-from twisted.internet.error import ConnectionRefusedError, CannotListenError
+from twisted.internet.error import CannotListenError
 from twisted.spread import pb
 from pathlib import Path
 
@@ -30,7 +30,7 @@ def _init_register(virt_root, my_name: str, node: NetQASMFactory):
     _setup_netqasm_server(my_name, node)
 
 
-def _connect_to_virt_node(my_name: str, netqasm_factory: NetQASMFactory, virtual_network: SocketsConfig, attempt: int = 0):
+def _connect_to_virt_node(my_name: str, netqasm_factory: NetQASMFactory, virtual_network: SocketsConfig, attempt: int):
     """Tries to connect to local virtual node.
 
     If connection is refused, we try again after a set amount of time
@@ -178,7 +178,7 @@ def start_qnodeos(node_name: str, network_config_file: Path, network_name: str):
 
     # Connect to the local virtual node simulating the "local" qubits
     logger.debug(f"START_QNODEOS: Connect to virtual node {node_name}")
-    _connect_to_virt_node(node_name, netqasm_factory, virtual_network)
+    _connect_to_virt_node(node_name, netqasm_factory, virtual_network, 0)
 
     # Run reactor
     reactor.run()

simulaqron/virtual_node/virtual.py

@@ -318,7 +318,6 @@ def handle_connection_error(self, reason, node: Host):
                 self._attempt = self._attempt + 1
                 reactor.callLater(simulaqron_settings.conn_retry_time, self.connect_to_node, node)
 
-
     def _get_virtual_id(self):
         """
         This is a crude and horrible cludge to generate unique IDs for virtual qubits.