T_CAPABILITY_REQ - protocol capability acknowledgment
This message consists of an M_PROTO or M_PCPROTO message containing a struct T_capability_req which contains (at least) the following members:
int32_t PRIM_type; /* always T_CAPABILITY_REQ */ /* must be the first field! */ uint32_t CAP_bits1; /* capability bits #1 */
This primitive notifies the provider that the user requests certain provider information and capabilities, and that it can make use of various TPI features as encoded in the CAP_bits1 field (see below).
The fields of this message have the following meanings:
- PRIM_type
This indicates the primitive type and is always T_CAPABILITY_REQ. This field must be strictly the first field to allow receivers to determine the message type.
- CAP_bits1
This is a 32-bit field with zero or more of the following bits set, all other bits must be zero:
- TC1_INFO
If set, his bit requests the provider information as if the T_CAPABILITY_REQ were a T_INFO_REQ.
- TC1_ACCEPTOR_ID
If set, this bit requests that the provider supply an acceptor identifier for use in a T_CONN_RES.
- Extensibility
In addition the following bit is reserved for future use: TC1_CAP_BITS2.This bit may later be used to enable another 32 capability bits, but must not currently be set.
This primitive may be sent at any time. It can be sent as either an M_PROTO or M_PCPROTO, and must be responded to with the same message type as itself.
Both connection-mode and connectionless-mode.
Transport user.
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