HP-UX SNAplus2 R7 APPC Programmer's Guide

APPC Conversation Verbs
MC_ALLOCATE and ALLOCATE
AP_INVALID_VERB
AP_TP_BUSY
AP_UNEXPECTED_SYSTEM_ERROR
WINDOWS
AP_COMM_SUBSYSTEM_NOT_LOADED
AP_STACK_TOO_SMALL
AP_INVALID_VERB_SEGMENT
APPC does not return secondary return codes with these primary return codes.
4.1.5 State When Issued
The conversation can be in any state except Reset when the TP issues this verb.
4.1.6 State Change
The conversation state does not change for this verb.
4.2 MC_ALLOCATE and ALLOCATE
The MC_ALLOCATE or ALLOCATE verb is issued by the invoking TP. This verb allocates a session between
the local LU and partner LU and (in conjunction with the RECEIVE_ALLOCATE verb) establishes a conversation
between the invoking TP and the invoked TP.
The MC_ALLOCATE verb establishes a mapped conversation. The ALLOCATE verb can establish either a basic
or mapped conversation. The use of the ALLOCATE verb to establish a mapped conversation enables the TP to
use basic conversation verbs to communicate with a mapped-conversation partner TP.
Upon successful execution of this verb, APPC generates a conversation identifier (
conv_id). This identifier is a re-
quired parameter for all other APPC conversation verbs.
The [MC_]ALLOCATE request will not usually be sent to the partner LU immediately; it will be queued at the
local LU until a full buffer can be sent. This means that errors in allocating a conversation are usually not reported
on the [MC_]ALLOCATE verb but on a subsequent verb.
4.2.1 VCB Structure: MC_ALLOCATE
UNIX
The definition of the VCB structure for the MC_ALLOCATE verb is as follows:
typedef struct mc_allocate
{
AP_UINT16 opcode;
unsigned char opext;
unsigned char format;
AP_UINT16 primary_rc;
AP_UINT32 secondary_rc;
unsigned char tp_id[8];
AP_UINT32 conv_id;
unsigned char reserv3;
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