On macOS (and Windows), /proc is unavailable so _get_process_start_time()
always returns None. When a gateway creates a scoped lock record with
start_time=None and then exits, macOS can reuse that PID for an unrelated
process. On restart, acquire_scoped_lock() sees:
1. os.kill(pid, 0) succeeds (PID is alive — but it's bluetoothuserd, not
the gateway)
2. existing.start_time is None and current_start is None, so the
start_time comparison is inconclusive
3. The lock is treated as active, blocking gateway startup with:
"Telegram bot token already in use (PID 873). Stop the other gateway
first."
Root cause: _read_process_cmdline() only reads /proc/<pid>/cmdline, which
doesn't exist on macOS. It always returns None, making
_looks_like_gateway_process() always return False, so the cmdline fallback
path in acquire_scoped_lock() was unreachable on macOS.
Fix (two parts):
1. _read_process_cmdline(): Add a ps(1) fallback for platforms without
/proc. When /proc/<pid>/cmdline doesn't exist, we now run
"ps -p <pid> -o command=" to retrieve the process command line. The
/proc path is tried first (preserving Linux performance); ps is only
invoked as a fallback.
2. acquire_scoped_lock(): When both the lock record's start_time and the
live process's start_time are None (the macOS case), fall back to
checking whether the live PID still looks like a Hermes gateway process
via _looks_like_gateway_process(). If it doesn't, the lock is stale.
Closes#16376
653d304290