[FieldTrip] Issue with Loading OPM FIF Files (fiff_dir_tree_find Failure)

[Daeun Gwon]

I hope you are doing well. I am writing to report an issue related to
loading our OPM data (FIF format) using both MATLAB (FieldTrip) and Python
(MNE).

*Issue Summary*

   -

   Some FIF files recorded in the *same experiment session* fail to load
   properly.
   -

   The end portion of the data appears truncated when loaded.
   -

   This occurs identically in both MATLAB and Python, while certain PCs
   load all files without any issues. This suggests that the data files
   themselves are not corrupted.

*Technical Details*

   -

   In MATLAB, we confirmed that the problem occurs inside the
   fiff_setup_read_raw function, specifically at line 79 where
   fiff_dir_tree_find is called.
   -

   For files that fail to load, the raw.dir structure contains corrupted
   values.
   -

      Normally, values such as kind and type are consistent integers
(e.g., kind
      = 300, type = 4).
      -

      In problematic files, the last entry contains abnormal values (e.g., kind
      = -113471426, type = -1.103131550000000e+09).
      -

   The implementation of fiff_dir_tree_find does not show abnormalities,
   making debugging difficult.
   -

   We are using the latest FieldTrip version cloned from GitHub and the
   fieldtrp Web's download

If you could provide any guidance or suggestions for further debugging, or
if you are aware of similar cases, your help would be greatly appreciated.

Thank you very much in advance.

Best regards,
Daeun Gwon

-- 
Daeun Gwon (Ph.D.)
Dept. of Computer Science and Electrical Engineering
Handong Global University (HGU), South Korea
Homepage: https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fbuly.kr%2F74W1jXo&data=05%7C02%7Cfieldtrip%40science.ru.nl%7Cbcd93d4d68474ac6380608de2ca6a0ef%7C084578d9400d4a5aa7c7e76ca47af400%7C1%7C0%7C638997291595626659%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C40000%7C%7C%7C&sdata=RvHzk4joTXQ3SFgbLnBOypaDl61gMrT7d6dQxiUfyzc%3D&reserved=0
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