Check for parallel download right before opening file for write

src/download.py

@@ -261,6 +261,7 @@ async def download_sceenshots(vi: VideoInfo) -> DownloadResult:
 async def download_video(vi: VideoInfo) -> DownloadResult:
     dwn = VideoDownloadWorker.get()
     retries = 0
+    exact_quality = False
     ret = DownloadResult.SUCCESS
     skip = Config.dm == DOWNLOAD_MODE_SKIP
     status_checker = ThrottleChecker(vi)
@@ -363,6 +364,12 @@ async def download_video(vi: VideoInfo) -> DownloadResult:
             total_str = f' / {vi.expected_size / Mem.MB:.2f}' if file_size else ''
             Log.info(f'Saving{starting_str} {vi.sdname} {content_len / Mem.MB:.2f}{total_str} Mb to {vi.sffilename}')
 
+            if Config.continue_mode and exact_quality:
+                proc_str = is_file_being_used(vi.my_fullpath)
+                if proc_str:
+                    Log.error(f'Error: file {vi.sffilename} already exists and is locked by \'{proc_str}\'!! Parallel download? Aborted!')
+                    return DownloadResult.FAIL_ALREADY_EXISTS
+
             dwn.add_to_writes(vi)
             vi.set_state(VideoInfo.State.WRITING)
             status_checker.run()

src/version.py

@@ -9,7 +9,7 @@
 APP_NAME = 'NM'
 APP_VER_MAJOR = '1'
 APP_VER_SUB = '8'
-APP_REVISION = '441'
+APP_REVISION = '442'
 APP_VERSION = f'{APP_VER_MAJOR}.{APP_VER_SUB}.{APP_REVISION}'
 
 #