CLI initialisation issues on Windows (serial monitor)

[Hannes7eicher]

Describe the problem

When uploading this code snippet to the Nano ESP32 nothing gets printed when opening the serial monitor.

void setup() {
  Serial.begin(9600);
  while(!Serial);
  Serial.println("Starting...");
}

void loop() {}

When opening the serial monitor with putty the prompt is printed as expected.

To reproduce

Upload a sketch to the Nano ESP32 either using the IDE or cli that uses while(!serial) and prints messages when opening the serial monitor. Open the serial monitor.

Expected behavior

When opening the serial monitor I expect to see the messages printed inside setup.

Arduino CLI version

0.34.2 Commit: 963c1a7 Date: 2023-09-11T10:05:41Z

Operating system

Windows

Operating system version

Windows 11 Pro

Additional context

No response

Issue checklist

• I searched for previous reports in the issue tracker
• I verified the problem still occurs when using the nightly build
• My report contains all necessary details

[cmaglie]

@Hannes7eicher I see a bizarre behavior, the Starting... message appears if I open the port two times in a row:

C:\Users\cmagl\Desktop\Test>..\arduino-cli.exe monitor -p COM12
Connesso a COM12! Premere CTRL-C per uscire.
^C

C:\Users\cmagl\Desktop\Test>..\arduino-cli.exe monitor -p COM12
Connesso a COM12! Premere CTRL-C per uscire.
Starting...

On the second try the Starting... message is triggered as expected. This is not happening with putty that shows the correct behavior. Is this happening also with your system?

I cannot reproduce it on my Linux box either, so this is a Windows-related bug.

[cmaglie]

The problem might be fixed with this patch: bugst/go-serial#174

[Xayton]

Need to release the new version of the serial-monitor in the package index.

[cmaglie]

Fixed by releasing of serial-monitor 0.14.1 on main package index.