No more console windows flashing on Windows when rdc runs

src/rdc/_platform.py

@@ -13,7 +13,7 @@
 import sys
 from collections.abc import Callable
 from pathlib import Path
-from typing import Any
+from typing import TypedDict
 
 _WIN: bool = sys.platform == "win32"
 _MAC: bool = sys.platform == "darwin"
@@ -72,7 +72,7 @@ def terminate_process_tree(pid: int) -> bool:
     """Kill a process and all its children (Windows: taskkill /T, Unix: SIGTERM).
 
     On Windows, .venv trampoline scripts spawn a child python process.
-    DETACHED_PROCESS prevents kill cascading, so we use taskkill /F /T
+    Detached daemons are not killed with their parent, so we use taskkill /F /T
     to terminate the entire process tree.
     """
     if pid <= 0:
@@ -83,6 +83,7 @@ def terminate_process_tree(pid: int) -> bool:
                 ["taskkill", "/F", "/T", "/PID", str(pid)],
                 capture_output=True,
                 timeout=5,
+                **hidden_kwargs(),
             )
             return result.returncode == 0
         except Exception:  # noqa: BLE001
@@ -176,13 +177,26 @@ def secure_dir_permissions(path: Path) -> None:
         path.chmod(0o700)
 
 
-def popen_flags() -> dict[str, Any]:
+class _SubprocessKwargs(TypedDict, total=False):
+    creationflags: int
+
+
+def popen_flags() -> _SubprocessKwargs:
     """Return extra kwargs for subprocess.Popen on this platform."""
     if _WIN:  # pragma: no cover
-        # DETACHED_PROCESS (0x8): detach from parent console
+        # CREATE_NO_WINDOW (0x08000000): hidden console that grandchildren inherit.
+        #   Not DETACHED_PROCESS: a console-less daemon makes every console child
+        #   (probe, taskkill) allocate its own visible window.
         # CREATE_NEW_PROCESS_GROUP (0x200): isolate signal handling
         # CREATE_BREAKAWAY_FROM_JOB (0x01000000): escape sshd job object
-        return {"creationflags": 0x00000008 | 0x00000200 | 0x01000000}
+        return {"creationflags": 0x08000000 | 0x00000200 | 0x01000000}
+    return {}
+
+
+def hidden_kwargs() -> _SubprocessKwargs:
+    """Return subprocess kwargs that stop console children opening a window on Windows."""
+    if _WIN:  # pragma: no cover
+        return {"creationflags": 0x08000000}  # CREATE_NO_WINDOW
     return {}
 
 
@@ -196,6 +210,7 @@ def find_pid_by_port(port: int) -> int:
             capture_output=True,
             text=True,
             timeout=5,
+            **hidden_kwargs(),
         )
         for line in result.stdout.splitlines():
             # Match: TCP  127.0.0.1:PORT  0.0.0.0:0  LISTENING  PID

src/rdc/commands/android.py

@@ -14,6 +14,7 @@
 
 import click
 
+from rdc import _platform
 from rdc.capture_core import run_target_control_loop
 from rdc.discover import find_renderdoc
 from rdc.remote_core import connect_remote_server
@@ -62,6 +63,7 @@ def _get_forwarded_port(serial: str | None, url: str) -> int | None:
             timeout=3,
             capture_output=True,
             text=True,
+            **_platform.hidden_kwargs(),
         )
     except (subprocess.TimeoutExpired, OSError):
         return None
@@ -92,6 +94,7 @@ def _is_mali_device(ctrl: Any, url: str, serial: str | None) -> bool:
             timeout=3,
             capture_output=True,
             text=True,
+            **_platform.hidden_kwargs(),
         )
         prop = proc.stdout.strip().lower()
         return any(prop.startswith(p) for p in _MALI_PLATFORMS)
@@ -124,7 +127,9 @@ def _adb(serial: str, *args: str, timeout: int = 10) -> subprocess.CompletedProc
     cmd = ["adb", "-s", serial, *args]
     log.debug("adb: %s", " ".join(cmd))
     try:
-        return subprocess.run(cmd, timeout=timeout, capture_output=True, text=True)
+        return subprocess.run(
+            cmd, timeout=timeout, capture_output=True, text=True, **_platform.hidden_kwargs()
+        )
     except subprocess.TimeoutExpired as exc:
         msg = f"adb command timed out: {' '.join(cmd)}"
         raise RuntimeError(msg) from exc
@@ -242,6 +247,7 @@ def _resolve_serial(serial: str | None) -> str:
         timeout=5,
         capture_output=True,
         text=True,
+        **_platform.hidden_kwargs(),
     )
     serials = []
     for line in proc.stdout.strip().splitlines()[1:]:

src/rdc/commands/doctor.py

@@ -89,12 +89,18 @@ def _check_replay_support(module: Any | None) -> CheckResult:
 
 
 def _check_renderdoccmd() -> CheckResult:
+    from rdc import _platform
+
     cmd_path = find_renderdoccmd()
     if cmd_path is None:
         return CheckResult("renderdoccmd", False, "not found in PATH or known paths")
     try:
         out = subprocess.run(
-            [str(cmd_path), "--version"], capture_output=True, text=True, timeout=3
+            [str(cmd_path), "--version"],
+            capture_output=True,
+            text=True,
+            timeout=3,
+            **_platform.hidden_kwargs(),
         )
         version = out.stdout.strip() or out.stderr.strip() or "unknown"
     except Exception:  # noqa: BLE001
@@ -170,6 +176,8 @@ def _check_win_vs_build_tools() -> CheckResult:
     if sys.platform != "win32":
         return CheckResult("win-vs-build-tools", True, "n/a")
 
+    from rdc import _platform
+
     vswhere = Path(r"C:\Program Files (x86)\Microsoft Visual Studio\Installer\vswhere.exe")
     if not vswhere.exists():
         found = shutil.which("vswhere")
@@ -196,6 +204,7 @@ def _check_win_vs_build_tools() -> CheckResult:
             capture_output=True,
             text=True,
             timeout=5,
+            **_platform.hidden_kwargs(),
         )
         installs: list[dict[str, Any]] = json.loads(proc.stdout or "[]")
     except subprocess.TimeoutExpired:

src/rdc/commands/session.py

@@ -44,6 +44,7 @@ def _adb_forwarded_port(serial: str) -> int | None:
             capture_output=True,
             text=True,
             timeout=5,
+            **_platform.hidden_kwargs(),
         )
     except (FileNotFoundError, subprocess.TimeoutExpired):
         return None

src/rdc/discover.py

@@ -119,6 +119,7 @@ def _probe_candidate(directory: str, timeout: float = 5.0) -> ProbeOutcome:
             capture_output=True,
             text=True,
             timeout=timeout,
+            **_platform.hidden_kwargs(),
         )
     except subprocess.TimeoutExpired:
         return ProbeOutcome(ProbeResult.TIMEOUT, directory)

tests/unit/test_platform.py

@@ -14,6 +14,7 @@
 from rdc._platform import (
     data_dir,
     find_pid_by_port,
+    hidden_kwargs,
     install_shutdown_signal,
     is_pid_alive,
     join_cmdline,
@@ -338,16 +339,20 @@ def test_windows_flags_present(self, monkeypatch: pytest.MonkeyPatch) -> None:
         monkeypatch.setattr("rdc._platform._WIN", True)
         result = popen_flags()
         flags = result["creationflags"]
-        assert flags & 0x00000008  # DETACHED_PROCESS
+        assert flags & 0x08000000  # CREATE_NO_WINDOW (own hidden console)
         assert flags & 0x00000200  # CREATE_NEW_PROCESS_GROUP
         assert flags & 0x01000000  # CREATE_BREAKAWAY_FROM_JOB
 
-    def test_windows_no_create_no_window(self, monkeypatch: pytest.MonkeyPatch) -> None:
-        """DS-02: CREATE_NO_WINDOW must NOT be set (mutually exclusive with DETACHED_PROCESS)."""
+    def test_windows_not_detached(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        """DS-02: DETACHED_PROCESS must NOT be set (console children would flash windows)."""
         monkeypatch.setattr("rdc._platform._WIN", True)
-        result = popen_flags()
-        flags = result["creationflags"]
-        assert not (flags & 0x08000000)  # CREATE_NO_WINDOW must NOT be set
+        assert not (popen_flags()["creationflags"] & 0x00000008)
+
+    def test_hidden_kwargs(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        monkeypatch.setattr("rdc._platform._WIN", False)
+        assert hidden_kwargs() == {}
+        monkeypatch.setattr("rdc._platform._WIN", True)
+        assert hidden_kwargs() == {"creationflags": 0x08000000}
 
 
 # ── Group H: renderdoc_search_paths() ────────────────────────────────