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File system API frames Local File System Request - 0x3B
Digi XBee® 3 Cellular LTE-M/NB-IoT Global Smart Modem User Guide 295
Offset Size Frame Field Description
7 16-bit
Directory
Handle
Value returned in initial Directory Open Response.
9 32-bit
File Size/Entry
Flags File's size in lower 24 bits, combined with the
following flags:
n
0x80000000 (ENTRY_IS_DIR): Entry is a
directory.
n
0x40000000 (ENTRY_IS_SECURE): File is
secure (write-only).
n
0x01000000 (ENTRY_IS_LAST): This is the last
entry.
n
Other flags in the top 8 bits (0x3E) are
currently reserved and set to zero.
13-n variable
Entry Name
File or directory name.
If there is enough room in the frame, there may be additional entries after the first.
n+1 8-bit
Null
Terminator
0x00 byte to separate entries
n+2 32-bit
File Size and
Flags Refer to description above .
n+6 variable
Entry Name Refer to description above .
Process the entries in a Directory Open Response or Directory Read Response as follows:
n
Split the File Size and Flags field into separate File Size and Flags .
n
Look for a null terminator after the File Size and Flags field.
n
Extract Entry Name as bytes after File Size and Flags and before either the null terminator or
the end of the frame.
n
Repeat this sequence if Entry Name had a null terminator and the packet contains
unprocessed entries.
n
If the final entry of the frame does not have ENTRY_IS_LAST set, send another Directory Read
Request to get additional entries.
Directory Close - 0x12
Description
The host can send this frame to indicate that it is done reading the directory and no longer needs the
Directory Handle . Note that the Directory Handle is automatically closed and no longer valid after
receiving a Response with the ENTRY_IS_LAST flag set.