Dead links (gofile notFound/404, 0807 404/410) fail immediately without retry

dlphelper/zero807.py

@@ -29,6 +29,10 @@ class Zero807Error(Exception):
     """Base error for 0807 downloads."""
 
 
+class Zero807NotFound(Zero807Error):
+    """The file no longer exists (HTTP 404/410). Not retryable."""
+
+
 def target_name(url: str) -> str:
     """Derive the filename from the URL path (e.g. /6saCNie.zip -> 6saCNie.zip)."""
     name = Path(urlparse(url).path).name
@@ -71,7 +75,11 @@ def download(
     proc = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)
     if proc.returncode != 0:
         tail = [line for line in proc.stderr.strip().splitlines() if line][-3:]
-        raise Zero807Error(f"curl exit code {proc.returncode}: {' | '.join(tail)}")
+        stderr = " | ".join(tail)
+        # -f makes curl exit 22 on any HTTP error; dead links fail for good
+        if "404" in stderr or "410" in stderr:
+            raise Zero807NotFound(f"dead link (HTTP 404/410): {stderr}")
+        raise Zero807Error(f"curl exit code {proc.returncode}: {stderr}")
 
     size = tmp.stat().st_size if tmp.exists() else 0
     if size == 0: