emrg: remove emrgd.pid entirely — fixed-port probe + cmdline scan for daemon liveness/kill (rant 2026-08-21T16:45:06)

[argszero]

Problem (rant 2026-08-21T16:45:06)

emrgd.pid no longer serves any purpose after #918 switched the GUI liveness check to a fixed-port TCP probe — the fixed port 56031 is the daemon's only ground truth (rant 2026-08-19T08:05:21; connect.py is_server_running_sync is already a TCP probe). The pid file was itself the root cause of repeated misjudgments/mis-deletions (#918 fixed the GUI side, but the file was still written/read in daemon.py / _stop_all.py).

Changes

1. emrg/server/daemon.py — deleted the startup emrgd.pid write (was "diagnostics only") and the shutdown self-delete step; _shutdown_all() dropped its pid_file parameter.
2. emrg/_stop_all.py:
   • deleted _read_pid_file()
   • stop_daemon(): ws shutdown → wait on fixed-port TCP probe (_port_is_open) → cmdline-scan kill fallback (_daemon_scan_pids, matches -m emrg.server) → token cleanup once the port is confirmed closed
   • added _port_is_open() (mirrors connect.py is_server_running_sync, pure stdlib for the standalone installer) and _daemon_scan_pids() (POSIX ps-scan filtered by new _EMRG_SERVER_RE; Windows reuses the CIM scan with server_only=True)
   • _scan_windows_python_emrg() gained a server_only param (filter -m emrg\.server vs -m emrg)
   • verify() daemon residual is now the port probe (previously _read_pid_file + _pid_alive)
   • module header docstring updated
3. emrg/gui/daemon_client.js — comment cleanup only (already port-probe since emrg: GUI daemon liveness — fixed-port TCP probe, never delete healthy daemon's token (rant 2026-08-21T15:26:42) #918).
4. Grep confirmed no other emrgd.pid readers/writers in scheduler.py / __main__.py / connect.py.

Tests

• tests/test_daemon.py: pid-file assertions removed/negated (no pid file may be written); _shutdown_all() calls updated to the no-arg signature
• tests/test_stop_all.py: TestPidFile → TestPortIsOpen (3) + TestDaemonScanPids (4, incl. POSIX daemon-only filter + Windows server_only delegation); verify tests patch _port_is_open instead of _read_pid_file
• tests/test_installer_stop.py: wiring assertions now check _port_is_open / _daemon_scan_pids / _EMRG_SERVER_RE
• Python test count 995 → 1001 (net +6); Agent.md doc-count guard synced; GUI 257 unchanged

Verification

emrg stop now handles alive / half-dead / missing-pid scenarios via port probe + cmdline scan; full suite green (pytest 1000 passed + 1 skipped, GUI 249 + 8); no emrgd.pid reads/writes remain anywhere in emrg/.

[argszero]

✅ LGTM — cycle 1214. emrgd.pid fully removed: daemon.py no longer writes/cleans it; _stop_all.py uses fixed-port TCP probe (_port_is_open) for liveness + cmdline scan (_daemon_scan_pids, -m emrg.server) for the kill fallback; verify() residual is port-based. Positive/negative states covered (port open/closed, POSIX daemon-only filter, Windows server_only delegation). Full suite green locally (pytest 1000+1, GUI 249+8), CI test + test-windows PASS.

[argszero]

✅ LGTM — cycle

2nd review (head 980c8e6, MERGEABLE/CLEAN, CI test + test-windows PASS):

• Fresh local verification on this branch: pytest 1000 passed + 1 skipped (1001 collected, matches Agent.md sync), GUI npm test 257 (249 pass / 0 fail / 8 skipped), import + CLI OK.
• emrgd.pid fully removed: daemon.py no longer writes/cleans it; _shutdown_all() dropped the pid_file param; grep confirms zero emrgd.pid readers/writers in emrg/ (only comments).
• _port_is_open() mirrors connect.py is_server_running_sync (stdlib socket, standalone-safe); _daemon_scan_pids() scans '-m emrg.server' cmdlines (POSIX ps + Windows CIM server_only) for the kill fallback; verify() daemon residual is now the port probe.
• Tests: TestPidFile → TestPortIsOpen (3) + TestDaemonScanPids (4, incl. POSIX daemon-only filter + Windows server_only delegation); installer wiring asserts the new symbols.
• Completes the #918 direction: fixed port is the sole ground truth for daemon liveness.

2/3.

[argszero]

✅ LGTM — cycle 1215. Independent re-review on head 980c8e6 (MERGEABLE, CI test + test-windows PASS):

• emrgd.pid fully gone from code: daemon.py no longer writes/cleans it, _shutdown_all() dropped the pid_file param; only comments + the deliberate negative-state GUI test (writes a pid file, asserts the port probe stays authoritative) remain.
• _port_is_open() = fixed-port TCP probe (127.0.0.1:56031) mirroring connect.py is_server_running_sync; used for the ws-grace wait, token cleanup gate, and verify() residual — port is the sole liveness ground truth.
• _daemon_scan_pids() = daemon-only cmdline identity (-m emrg.server): POSIX ps-scan filtered by _EMRG_SERVER_RE (excludes TUI -m emrg), Windows CIM scan with server_only=True. TUI clients are stopped earlier in the chain, so the daemon-only kill fallback is safe.
• Tests: TestPortIsOpen (open/refused/OSError), TestDaemonScanPids (TUI-vs-daemon filter, own-pid exclusion, Windows server_only delegation + CIM filter), verify residual rewritten to the port probe.
• Local: pytest 1000 passed + 1 skipped (matches Agent.md sync on this branch), import + CLI OK.