2.2.4.3.2 Server Response Extensions

A successful response takes the following format. These extensions allocate the first two bytes of the SMB_Parameters.Words.Reserved field for use as the CountHigh field. This field is used when the CAP_LARGE_WRITEX capability has been negotiated to allow for file writes larger than 0xFFFF bytes in length. All other fields are defined as specified in [MS-CIFS] section 2.2.4.43.2.

 SMB_Parameters
   {
   UCHAR WordCount;
   Words
     {
     UCHAR  AndXCommand;
     UCHAR  AndXReserved;
     USHORT AndXOffset;
     USHORT Count;
     USHORT Available;
     USHORT CountHigh;
     USHORT Reserved;
     }
   }
 SMB_Data
   {
   USHORT ByteCount;
   }

SMB_Parameters

Words (12 bytes):

0	1	2	3	4	5	6	7	8	9	1 0	1	2	3	4	5	6	7	8	9	2 0	1	2	3	4	5	6	7	8	9	3 0	1
AndXCommand								AndXReserved								AndXOffset
Count																Available
CountHigh																Reserved

CountHigh (2 bytes): This field contains the two most significant bytes of the count of bytes written. If the number of bytes written is greater than or equal to 0x00010000( 64 kilobytes), then the server MUST set the two least significant bytes of the length in the Count field of the request and the two most significant bytes of the length in the CountHigh field.

Reserved (2 bytes): This field is reserved. Servers MUST set this field to zero and clients MUST ignore this field upon receipt.