DOSFS and the short and Long file names.

Nasir, Aliasgar ( SBU-ETS ) aliasgar.nasir at
Thu Aug 4 03:59:04 UTC 2011


With the RTEMS4.10, we noticed that there is concept about long and short file names in the DOSFS.
We use the DOSFS on an SDCARD. When we try to write a file on the card, with file name say 'Error2.txt', the DOSFS detects this as a long file name and then executes the below code in function msdos_find_name_in_fat_file(), while creating the file.

    if (name_type == MSDOS_NAME_LONG)
        int      slot = (((empty_space_offset * bts2rd) + empty_space_entry) /
                         MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE) + lfn_entries + 1;
        msdos_short_name_hex(MSDOS_DIR_NAME(name_dir_entry), slot);
The above piece of code modifies the file name as ERR~0005.TXT. This is the file name seen when we see the contents of the card on a Windows based machine using card reader. The file name of the file as seen from the RTEMS shell is still 'Error2.txt'

Can anyone guide as what should be done to see a the correct file name (Error2.txt) on the Windows machine?


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