fix(agents): in_use_hints lists the processes holding the conversation file (lsof) (#78)

.agents/skills/lib_py/agents/base.py

@@ -1,7 +1,7 @@
 # base.py — BaseAgentAdapter abstract base class, SpawnSpec, and DiscoveryContext
 
 import os, json, sqlite3, shutil, subprocess, tempfile
-from typing import Optional, Dict, Any, List
+from typing import Optional, Dict, Any, List, Tuple
 from urllib.parse import quote
 from lib_py.paths import resolve_home
 from lib_py.verify_session import verify_session_uuid, workspace_key
@@ -86,6 +86,34 @@ def conversation_in_use(uuid: str, paths=()) -> bool:
     return False
 
 
+def file_holders(paths=()) -> List[Tuple[int, str]]:
+    """(pid, command_line) for each process holding one of `paths` open via lsof (#78).
+    Informational only: returns [] when lsof is absent or fails."""
+    existing = [p for p in paths if p and os.path.exists(p)]
+    if not existing or not shutil.which("lsof"):
+        return []
+    try:
+        r = subprocess.run(["lsof", "-t"] + existing, capture_output=True, text=True, timeout=10)
+    except Exception:
+        return []
+    pids: List[int] = []
+    for tok in (r.stdout or "").split():
+        if tok.isdigit():
+            pid = int(tok)
+            if pid not in pids:
+                pids.append(pid)
+    out: List[Tuple[int, str]] = []
+    for pid in pids:
+        try:
+            cmd = subprocess.run(["ps", "-o", "command=", "-p", str(pid)],
+                                 capture_output=True, text=True, timeout=10).stdout.strip()
+        except Exception:
+            continue
+        if cmd:
+            out.append((pid, cmd))
+    return out
+
+
 def _plausible_id(uuid: str) -> bool:
     """An id safe to build a path from and to search for: not empty, not
     made of dots alone ("." names the parent dir itself), no "/", ".." or "*"."""
@@ -354,14 +382,25 @@ class BaseAgentAdapter:
         path = self.artifact_path(uuid, ctx)
         return uuid in path and os.path.exists(path)
 
+    def in_use_paths(self, uuid: str, ctx: DiscoveryContext) -> list:
+        """On-disk paths checked with lsof for conversation_in_use and in_use_hints (#78)."""
+        return [self.artifact_path(uuid, ctx)]
+
+    def _holder_counts(self, cmd: str) -> bool:
+        return True
+
     def conversation_in_use(self, uuid: str, ctx: DiscoveryContext) -> bool:
         """True while a live process still references the conversation."""
-        return conversation_in_use(uuid, [self.artifact_path(uuid, ctx)])
+        return conversation_in_use(uuid, self.in_use_paths(uuid, ctx))
 
     def in_use_hints(self, uuid: str, ctx: DiscoveryContext) -> list:
         """Where to look for what holds the conversation, shown when a purge
         is refused because it is in use."""
-        return [f"any process with it on its command line (an editor, a grep, ...): ps -axww | grep {uuid}"]
+        hints = [f"any process with it on its command line (an editor, a grep, ...): ps -axww | grep {uuid}"]
+        for pid, cmd in file_holders(self.in_use_paths(uuid, ctx)):
+            if self._holder_counts(cmd):
+                hints.append(f"held open by pid {pid}: {cmd}  (not stopped by MAM; end it yourself if it is safe)")
+        return hints
 
     def spawn_spec(self, binary: str, session_uuid: str = "", use_wrapper: bool = False) -> str:
         raise NotImplementedError