Directory Open - 0x11

Description

Used with Directory Read to list files and directories in a given directory. To get a listing of entries in a directory:

1. Send a Directory Open Request.

2. Parse multiple entries from the Response.

3. If the last entry has the ENTRY_IS_LAST flag set, the listing is complete and the Directory Handle was automatically released.

4. If the listing is not complete, do one of the following:

   • Send a Directory Read Request to get additional directory entries

   • Send a Directory Close Request to release the Directory Handle.

Request

Offset	Size	Frame Field	Description
5	8-bit	File System Command	Directory Open 0x10
6	16-bit	Path ID	See command Get Path ID - 0x1C for description.
8-n	variable	Directory Name	Pathname relative to Path ID, or empty to get a file listing for the Path ID.

Success Response

A Directory Open Request sends a response identical to a Directory Read Request. An empty directory returns a single entry with only the ENTRY_IS_LAST flag set, and a 0-byte Entry Name. A response ending with an ENTRY_IS_LAST flag automatically closes the Directory Handle.

Offset	Size	Frame Field	Description
5	8-bit	File System Command	Directory Read - 0x13 or Directory Open - 0x11, depending on request.
6	16-bit	Status	Success - 0x00
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: 0x80000000 (ENTRY_IS_DIR): Entry is a directory. 0x40000000 (ENTRY_IS_SECURE): File is secure (write-only). 0x01000000 (ENTRY_IS_LAST): This is the last entry. 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:

• Split the File Size and Flags field into separate File Size and Flags.

• Look for a null terminator after the File Size and Flags field.

• Extract Entry Name as bytes after File Size and Flags and before either the null terminator or the end of the frame.

• Repeat this sequence if Entry Name had a null terminator and the packet contains unprocessed entries.

• If the final entry of the frame does not have ENTRY_IS_LAST set, send another Directory Read Request to get additional entries.