CONTENTS Title Page Copyright Page Preface 1 Introduction 1.1 Logical Unit Type 6.2 1.2 APPC/LU6.2 Programming Interface Features 1.3 SNA Concepts 1.4 Common Interface Transaction Programs 2 Concepts and Terms 2.1 Sessions and Conversations 2.1.1 Sessions 2.1.2 Conversations 2.1.2.1 Requesting a Session for a Conversation 2.1.2.2 Basic and Mapped Conversations 2.1.2.3 Generalized Data Stream (GDS) 2.1.2.4 Basic Conversations 2.1.2.5 Mapped Conversations 2.2 Sending Messages 2.2.1 Putting the VMS Transaction Program into the Send State 2.2.2 Submitting Data for Transmission 2.2.3 Transmitting the Send Buffer 2.3 Receiving a Request-to-Send Notification 2.4 Receiving a Message from the IBM Host Transaction Program 2.5 Confirmation Processing 2.6 Sending and Receiving Error Notification 2.7 Ending a Conversation 2.7.1 Normal Deallocation 2.7.2 Abnormal Deallocation 2.7.3 Local Deallocation 3 APPC/LU6.2 Programming Interface Features 3.1 Returning Status Information 3.1.1 Function Value Returns 3.1.2 The I/O Status Vector 3.1.3 Using Status Vectors 3.2 Program Initialization Parameters 3.2.1 Sending PIP Data to a Remote Transaction Program 3.2.2 Receiving PIP Data from Remote Transaction Program 3.3 Synchronous and Asynchronous Operation 3.3.1 Synchronous Mode 3.3.2 Asynchronous Mode 3.4 Session Activation 3.5 Session Deactivation 3.6 Security 3.7 Defining IBM Access Information 3.8 Contention Polarity 3.9 Outbound Conversations 3.10 Notification of Session Failure 3.11 Notification of Conversation Deallocation 3.12 LU Security Support 4 Procedure Calling Format: Conversation Verbs 4.1 SNALU62$ALLOCATE 4.1.1 Status Codes 4.1.2 Valid Conversation State for SNALU62$ALLOCATE 4.1.3 State Transition 4.2 SNALU62$CONFIRM 4.2.1 Status Codes 4.2.2 Valid Conversation State for SNALU62$CONFIRM 4.2.3 State Transition 4.3 SNALU62$CONFIRMED 4.3.1 Status Codes 4.3.2 Valid Conversation State for SNALU62$CONFIRMED 4.3.3 State Transition 4.4 SNALU62$DEALLOCATE 4.4.1 Status Codes 4.4.2 Valid Conversation States for SNALU62$DEALLOCATE 4.4.3 State Transition 4.5 SNALU62$FLUSH 4.5.1 Status Codes 4.5.2 Valid Conversation State for SNALU62$FLUSH 4.5.3 State Transition 4.6 SNALU62$GET_ATTRIBUTES 4.6.1 Status Codes 4.6.2 Valid Conversation States for SNALU62$GET_ATTRIBUTES 4.6.3 State Transition 4.7 SNALU62$GET_PIP 4.7.1 Status Codes 4.7.2 Valid Conversation State for SNALU62$GET_PIP 4.7.3 State Transition 4.8 SNALU62$GET_TYPE 4.8.1 Status Codes 4.8.2 Valid Conversation States for SNALU62$GET_TYPE 4.8.3 State Transition 4.9 SNALU62$POST_ON_RECEIPT 4.9.1 Status Codes 4.9.2 Valid Conversation State for SNALU62$POST_ON_RECEIPT 4.9.3 State Transition 4.10 SNALU62$PREPARE_TO_RECEIVE 4.10.1 Status Codes 4.10.2 Valid Conversation State for SNALU62$PREPARE_TO_RECEIVE 4.10.3 State Transition 4.11 SNALU62$RECEIVE_AND_WAIT 4.11.1 Status Codes 4.11.2 Valid Conversation States for SNALU62$RECEIVE_AND_WAIT 4.11.3 State Transition 4.12 SNALU62$RECEIVE_IMMEDIATE 4.12.1 Status Codes 4.12.2 Valid Conversation State for SNALU62$RECEIVE_IMMEDIATE 4.12.3 State Transition 4.13 SNALU62$REQUEST_TO_SEND 4.13.1 Status Codes 4.13.2 Valid Conversation States for SNALU62$REQUEST_TO_SEND 4.13.3 State Transition 4.14 SNALU62$SEND_DATA 4.14.1 Status Codes 4.14.2 Valid Conversation State for SNALU62$SEND_DATA 4.14.3 State Transition 4.15 SNALU62$SEND_ERROR 4.15.1 Status Codes 4.15.2 Valid Conversation States for SNALU62$SEND_ERROR 4.15.3 State Transition 4.16 SNALU62$SUPPLY_PIP 4.16.1 Status Codes 4.16.2 Valid Conversation States for SNALU62$SUPPLY_PIP 4.16.3 State Transition 4.17 SNALU62$WAIT 4.17.1 Status Codes 4.17.2 Valid Conversation State for SNALU62$WAIT 4.17.3 State Transition 5 Procedure Calling Format: Control Operator Verbs 5.1 SNALU62$ACTIVATE_SESSION 5.1.1 Status Codes 5.1.2 State Transition 5.2 SNALU62$DEACTIVATE_SESSION 5.2.1 Status Codes 5.3 SNALU62$DEFINE_REMOTE 5.3.1 Status Codes 5.4 SNALU62$DEFINE_TP 5.4.1 Status Codes 5.5 SNALU62$DELETE 5.5.1 Status Codes 6 Compiling and Linking a Transaction Program 6.1 Creating and Compiling Your Program 6.2 Linking Your Program to the Shareable Program Image A Summary of Parameter Notation B Programming Examples B.1 FORTRAN Programming Example B.2 Pascal Programming Example B.3 BASIC Programming Example B.4 MACRO Programming Example B.5 COBOL Programming Example B.6 PL/I Programming Example B.7 C Programming Example B.8 Second C Programming Example B.9 Third C Programming Example C Return Codes and State Changes C.1 Return Codes and State Changes for Conversations C.2 Return Codes for Control Operator Verbs D Conversation State Transitions D.1 Using the Conversion State Transitions table E APPC/LU6.2 Interface Procedures and Status Messages F Definitions for the APPC/LU6.2 Interface G APPC/LU6.2 Programming Interface Compatibility Features G.1 The SNALU62$DEFINE Procedure G.1.1 Undefining a Local LU Name G.1.2 Status Codes G.1.3 State Transition G.2 Status Codes G.3 Obsolete Definitions for the APPC/LU6.2 Programming Interface H Status Codes I Problem Solving Glossary FIGURES 1-1 APPC/LU6.2 Using DECnet/SNA Gateway Connection to IBM Host 1-2 APPC/LU6.2 Using VMS/SNA Connection to IBM Host 2-1 Basic Conversation Buffer 2-2 Mapped Conversation Buffer 3-1 I/O Status Vector TABLES A-1 Parameter Notation D-1 Conversion State Transition E-1 Status Messages G-1 LU Attribute Identifiers and Attributes