PAM Programming Manual

Link-Level Interfaces
PAM Programming Manual—142482
3-22
Formatting an Aggregate SDU Header (Token Ring)
ZL2TR^Frmt^SDU^Hdr^ primitive must be passed only aggregate SDU buffers that
have already been initialized by one of the two preceding primitives; otherwise
unpredictable results occur.
Formatting an Aggregate SDU Header (Token Ring)
Aggregate SDUs are created when the application determines that it needs to send one
or more SDUs to an LSAP and there is no aggregate SDU waiting to be sent. This
primitive initializes an aggregate SDU buffer and formats an aggregate SDU header.
The syntax for this primitive is
The parameters of this primitive are defined as follows:
Aggr^SDU^Buff^ptr (STRING .EXT)
Required input used to reference the buffer to be used for the aggregate SDU to the
L2TR Formatting Library.
Aggr^SDU^Buff^Size^B (INT)
Required input that tells the L2TR Formatting Library the size, in bytes, of the
buffer to be used for the aggregate SDU.
sdu^type (INT)
Required input that tells the L2TR Formatting Library which type of SDUs are to be
formatted in the buffer. Must be ZL2TR^VAL^SDUTYPE^LLC1.
sap^val
Required input that tells the network code where to send the data. The SAP value is
the value of a local SAP that has been opened.
The syntax for C programs is
INT PROC ZL2TR^Frmt^Aggr^SDU^Hdr^ ( AggrSDU^Buff^ptr,
,AggrSDU^Buff^Size^B,
,sdu^type,
,sap^val ) EXTENSIBLE;
short ZL2TR_FRMT_AGGR_SDU_HDR_( char *Ag_SDU_Buff_Ptr
,short Ag_SDU_Buff_Size_B
,short Sdu_Type
,short Sap_Val)