HP-UX SNAplus2 R7 APPC Programmer's Guide

Writing Transaction Programs
APPC Entry Points: Windows Systems
Supplied Parameters
SNAplus2 calls the callback routine with the following parameters:
vcb
Pointer to the VCB supplied by the application. The VCB now includes the returned parameters set by
SNAplus2.
tp_id
The 8-byte TP identifier of the TP in which the verb was issued.
conv_id
The conversation identifier of the conversation in which the verb was issued.
corr
The correlator value supplied by the application. This value enables the application to correlate the returned
information with its other processing.
The callback routine need not use all of these parameters. The callback routine can perform all the necessary
processing on the returned VCB, or it can simply set a variable to inform the main program that the verb has
completed.
Returned Values
The function does not return a value.
Using the Callback Routine for Asynchronous Verb Completion
When using the callback routine for asynchronous verb completion, the application can issue additional asynchronous
APPC verbs from within the callback routine, if required. SNAplus2 rejects any synchronous verbs issued
from within a callback routine with the primary and secondary return codes
AP_PARAMETER_CHECK
and
AP_SYNC_NOT_ALLOWED.
2.4 APPC Entry Points: Windows Systems
WINDOWS
A Windows application accesses APPC using the following entry points:
WinAPPCStartup
Registers the application as a Windows APPC user, and determines whether the APPC software supports the
level of function required by the application.
WinAsyncAPPC
Issues an APPC verb. The verb normally completes asynchronously and does not block; APPC indicates the
completion by posting a message to the application window.
WinAsyncAPPCEx
Issues an APPC verb. If the verb completes asynchronously, APPC indicates the completion by signaling an
event handle. Use this function instead of the blocking versions of the verbs to allow multiple sessions to be
handled on the same thread.
WinAPPCCancelAsyncRequest
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