id = 2843
title = "Strange stdin/out <-> console issue (paste problem) . May be char-win-stdio.c bug."
state = "opened"
created_at = "2025-02-26T11:33:58.282Z"
closed_at = "n/a"
labels = ["Chardev"]
url = "https://gitlab.com/qemu-project/qemu/-/issues/2843"
host-os = "Windows 10 22H2"
host-arch = "x86"
qemu-version = "9.2.50"
guest-os = "Linux|FreeBSD"
guest-arch = "x86"
description = """I was trying to execute QEMU with VM from command line(shell) and work inside a VM within that initial console. All goes well except... pasting from clipboard. Pastings from clipboard are truncated to somewhat less (no more) then a terminal width (in columns).

I understand that it seems to be far from QEMU but I tried different terminals/shells/guest systems with the same result. The only things remain the same - QEMU."""
reproduce = """In Windows open a console (shell). Run QEMU with guest serial attached to QEMU stdio. Try to paste some text. Pasted text will be truncated to 15-35 characters. Before QEMU run and after QEMU exit text pasted normally."""
additional = """-  Shell probed: **cmd**, **powershell**
- Terminals probed: **Windows Terminal**, **Alacritty**, **Wezterm**, **Windows Terminal Preview**
- Guest probed: **Alpine Linux**, **FreeBSD**
- Setting inside guest probed: various terminal speed/options via **stty**
- QEMU arguments probed: from **-nographics** to manually define **-chardev/-serial** with/without **-mon**.

Finally I gave up. But want to mention that there are may be bug in source. When I tried to study source to find a hint for my issue I found that (char-win-stdio.c, line 162):
```
is_console = GetConsoleMode(stdio->hStdIn, &dwMode) != 0;
    stdio->dwOldMode = dwMode;

    if (is_console) {
```

Documentation of **GetConsoleMode** function says:
```
Return value:

If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero.
```

If understand correctly **is_console** will always be _true_. It will be _false_ only in case of invalid **stdio->hStdIn**.

I don't how this is related to my issue just put here all info I have in hope of resolving."""