Compaq OSI/FTAM D43, OSI/APLMGR D43 manual File-Attribute Mappings, Kernel Group File Attributes

Compaq FTAM Responder Support of	File-Attribute Mappings
ISO FTAM Functions

strings may require you to increase the value of the maximum-string-length parameter in your requests. The following formula defines the conditions under which decoded data will fit into the buffer:

NS-1

Σ((ZLEN)i )+ ((26 + PAD) * NS) <= 25600 bytes i=0

where

NS	= number of character strings
ZLEN	= length in bytes of a given character string
PAD	= pad byte following string; if string length is even,
	PAD = 0; otherwise, PAD = 1

26= maximum data-header overhead per character string

When the responder retrieves data from the VFS in response to a read request, it automatically packages it into PDUs small enough to fit into its buffer. Therefore, no similar adjustments are necessary on read requests.

The formula for calculating the size of the encoded data is given below. This formula applies only to PDUs that contain primitive strings; PDUs containing constructed strings have additional overhead. As mentioned above, the encoded data limit is 16 KB.

NE-1

SIGMA((ZLEN)i )+ ((TAG + LEN) * NS) <= 16384 bytes (16 KB) i=0

where

NS	= number of character strings
ZLEN	= length in bytes of a given character string
TAG	= number of bytes used to encode the data tag
LEN	= number of bytes used to encode length of string

Note. When the Compaq responder encodes data, the maximum encoded-data header overhead (TAG + LEN) is always 4 bytes per string. (The same is true for data encoded by the Compaq initiator.) An FTAM configurable file cannot be opened by the responder.

File-Attribute Mappings

The following subsection maps FTAM virtual filestore file attributes to specific Guardian and NonStop SQL file attributes. File attributes provide information for various aspects of a file, such as file name, file size, date and time of file creation, and so on.

Kernel Group File Attributes

Every FTAM implementation must fully support kernel file attributes. The kernel group includes the filename, permitted-actions, and contents-type attributes.

OSI/FTAM Responder Manual—425199-001

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