See Also

326 Pages·2017·2.05 MB·English

Oracle® Tuxedo
Programming an Oracle Tuxedo ATMI Application Using C
11g Release 1 (11.1.1.3.0)
December 2011
Oracle Tuxedo Programming an Oracle Tuxedo ATMI Application Using C, 11g Release 1 (11.1.1.3.0)
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Contents
1. Introduction to Oracle Tuxedo Programming
Oracle Tuxedo Distributed Application Programming. . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Communication Paradigms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Oracle Tuxedo Clients. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Oracle Tuxedo Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
Basic Server Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
Servers as Requesters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8
Oracle Tuxedo API: ATMI. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8
2. Managing Typed Buffers
Overview of Typed Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Allocating a Typed Buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-7
Putting Data in a Buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-10
Resizing a Typed Buffer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-12
Checking for Buffer Type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-15
Freeing a Typed Buffer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-17
Using a VIEW Typed Buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-18
Setting Environment Variables for a VIEW Typed Buffer . . . . . . . . . . . . . . . . . .2-18
Creating a View Description File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-19
Executing the VIEW Compiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-23
Using an FML Typed Buffer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-25
Setting Environment Variables for an FML Typed Buffer. . . . . . . . . . . . . . . . . . .2-25
Programming an Oracle Tuxedo ATMI Application Using C iii
Creating a Field Table File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-25
Creating an FML Header File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-27
Using an XML Typed Buffer and the Apache Xerces C++ Parser . . . . . . . . . . . . . . . 2-29
About the XML Typed Buffer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-29
About the Apache Xerces C++ Parser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-30
XML Parser Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-30
XML Parser Support for ICU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-31
XML Parser Sample Application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-31
Xerces Schema Sample . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-31
Converting XML Data To and From FML/FML32 Buffers. . . . . . . . . . . . . . . . . 2-31
Using On-Demand Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-32
Using Automatic Conversion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-33
Mapping XML To and From FML/FML32 Field Types. . . . . . . . . . . . . . . . 2-36
Conversion Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-40
Using an MBSTRING Typed Buffer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-42
Multibyte Character Encoding Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-44
Enabling MBSTRING to be Self-describing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-48
Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-48
Safe/Unsafe Encoding Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-48
Multibyte Character Support Limitations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-49
Multibyte Character Encoding Support for libiconv. . . . . . . . . . . . . . . . . . . . . . . 2-49
Customizing a Buffer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-51
Defining Your Own Buffer Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-53
Coding Switch Element Routines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-61
Adding a New Buffer Type to tm_typesw. . . . . . . . . . . . . . . . . . . . . . . . . . . 2-62
Compiling and Linking Your New tm_typesw . . . . . . . . . . . . . . . . . . . . . . . 2-63
Compiling and Linking Your New tm_typesw for a 16-bit Windows Platform . .
2-65
iv Programming an Oracle Tuxedo ATMI Application Using C
Data Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-65
3. Programming Environment
Updating the UBBCONFIG Configuration File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Setting Environment Variables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
Including the Required Header Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Starting and Stopping the Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
4. Writing Clients
Joining an Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Using Features of the TPINIT Typed Buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Client Naming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Unsolicited Notification Handling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5
System Access Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Resource Manager Association. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Client Authentication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Leaving the Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
Building Clients . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8
See Also. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
Client Process Examples. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
5. Writing Servers
Oracle Tuxedo System main( ). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1
System-Supplied Server and Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
System-Supplied Server: AUTHSVR( ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
System-Supplied Services: tpsvrinit( ) Function. . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Receiving Command-line Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Opening a Resource Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
System-Supplied Services: tpsvrdone( ) Function. . . . . . . . . . . . . . . . . . . . . . . . . . 5-7
Programming an Oracle Tuxedo ATMI Application Using C v
Guidelines for Writing Servers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Defining a Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
Example: Checking the Buffer Type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-13
Example: Checking the Priority of the Service Request. . . . . . . . . . . . . . . . . . . . 5-14
Terminating a Service Routine. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-16
Sending Replies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-16
Invalidating Descriptors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-23
Forwarding Requests. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-24
Advertising and Unadvertising Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-28
Advertising Services. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-28
Unadvertising Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-29
Example: Dynamic Advertising and Unadvertising of a Service. . . . . . . . . . . . . 5-29
Building Servers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-30
See Also . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-32
Using a C++ Compiler. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-32
Declaring Service Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-32
Using Constructors and Destructors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-33
6. Writing Request/Response Clients and Servers
Overview of Request/Response Communication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Sending Synchronous Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
Example: Using the Same Buffer for Request and Reply Messages . . . . . . . . . . . 6-4
Example: Testing for Change in Size of Reply Buffer . . . . . . . . . . . . . . . . . . . . . . 6-5
Example: Sending a Synchronous Message with TPSIGRSTRT Set. . . . . . . . . . . 6-6
Example: Sending a Synchronous Message with TPNOTRAN Set. . . . . . . . . . . . 6-7
Example: Sending a Synchronous Message with TPNOCHANGE Set. . . . . . . . . 6-9
Sending Asynchronous Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11
Sending an Asynchronous Request. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11
vi Programming an Oracle Tuxedo ATMI Application Using C
Example: Sending an Asynchronous Message with TPNOTRAN | TPNOREPLY
6-13
Example: Sending Asynchronous Requests. . . . . . . . . . . . . . . . . . . . . . . . . . 6-14
Getting an Asynchronous Reply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-15
Setting and Getting Message Priorities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-16
Setting a Message Priority. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-16
Getting a Message Priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-18
7. Writing Conversational Clients and Servers
Overview of Conversational Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Joining an Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
Establishing a Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
Sending and Receiving Messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Sending Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Receiving Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Ending a Conversation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Example: Ending a Simple Conversation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9
Example: Ending a Hierarchical Conversation. . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
Executing a Disorderly Disconnect. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-11
Building Conversational Clients and Servers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-11
Understanding Conversational Communication Events. . . . . . . . . . . . . . . . . . . . . . . . 7-12
8. Writing Event-based Clients and Servers
Overview of Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Unsolicited Events. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Brokered Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Notification Actions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
EventBroker Servers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
System-defined Events. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
Programming an Oracle Tuxedo ATMI Application Using C vii
Programming Interface for the EventBroker. . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
Defining the Unsolicited Message Handler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Sending Unsolicited Messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Broadcasting Messages by Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Broadcasting Messages by Identifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7
Checking for Unsolicited Messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
Subscribing to Events. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
Notification via Unsolicited Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
Notification via Service Call or Reliable Queue . . . . . . . . . . . . . . . . . . . . . . 8-10
Unsubscribing from Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-11
Posting Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-12
Example of Event Subscription . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-14
9. Writing Global Transactions
What Is a Global Transaction?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
Starting the Transaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2
Suspending and Resuming a Transaction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-7
Suspending a Transaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
Resuming a Transaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-8
Example: Suspending and Resuming a Transaction. . . . . . . . . . . . . . . . . . . . . . . . 9-9
Terminating the Transaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-10
Committing the Current Transaction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-10
Prerequisites for a Transaction Commit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-10
Two-phase Commit Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-11
Aborting the Current Transaction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-12
Example: Committing a Transaction in Conversational Mode. . . . . . . . . . . . . . . 9-12
Example: Testing for Participant Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-14
Implicitly Defining a Global Transaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-15
viii Programming an Oracle Tuxedo ATMI Application Using C
Implicitly Defining a Transaction in a Service Routine . . . . . . . . . . . . . . . . . . . . 9-15
Defining Global Transactions for an XA-Compliant Server Group. . . . . . . . . . . . . . . 9-16
Testing Whether a Transaction Has Started. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-16
See Also. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-18
10. Programming a Multithreaded and Multicontexted ATMI
Application
Support for Programming a Multithreaded/Multicontexted ATMI Application . . . . . 10-2
Platform-specific Considerations for Multithreaded/Multicontexted Applications10-2
Planning and Designing a Multithreaded/Multicontexted ATMI Application. . . . . . . 10-3
What Are Multithreading and Multicontexting?. . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
What Is Multithreading?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-3
What Is Multicontexting?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Auditing a Multithreaded or Multicontexted Application. . . . . . . . . . . . . . . . . . . 10-7
Advantages and Disadvantages of a Multithreaded/Multicontexted ATMI Application
10-7
Advantages of a Multithreaded/Multicontexted ATMI Application . . . . . . . 10-7
Disadvantages of a Multithreaded/Multicontexted ATMI Application . . . . . 10-8
How Multithreading and Multicontexting Work in a Client. . . . . . . . . . . . . . . . . 10-9
Start-up Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-9
Work Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-11
Completion Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-13
How Multithreading and Multicontexting Work in Server-Dispatched Threads an on
ATMI Server. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-14
Start-up Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-14
Work Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-15
Completion Phase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-17
Programming an Oracle Tuxedo ATMI Application Using C ix
How Multithreading and Multicontexting Work in Application-Created Threads of an
ATMI Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-18
Start-Up Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-18
Work Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-19
Completion Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-19
See Also . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-20
Design Considerations for a Multithreaded and Multicontexted ATMI Application. .
10-20
Environment Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-20
Design Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-21
Interoperability Restrictions for Workstation Clients . . . . . . . . . . . . . . . . . 10-23
Implementing a Multithreaded/ Multicontexted ATMI Application. . . . . . . . . . . . . 10-24
Preliminary Guidelines for Programming a Multithreaded/Multicontexted ATMI
Application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-24
Prerequisites for a Multithreaded ATMI Application . . . . . . . . . . . . . . . . . 10-25
General Multithreaded Programming Considerations. . . . . . . . . . . . . . . . . 10-25
Concurrency Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-25
Writing Code to Enable Multicontexting in an ATMI Client . . . . . . . . . . . . . . . 10-27
Context Attributes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-27
Setting Up Multicontexting at Initialization . . . . . . . . . . . . . . . . . . . . . . . . 10-28
Implementing Security for a Multicontexted ATMI Client. . . . . . . . . . . . . 10-29
Synchronizing Threads Before an ATMI Client Termination . . . . . . . . . . . 10-29
Switching Contexts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-30
Handling Unsolicited Messages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-33
Coding Rules for Transactions in a Multithreaded/Multicontexted ATMI
Application. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-33
Writing Code to Enable Server-Dispatched Multicontexting and Multithreading
Threads in an ATMI Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-34
x Programming an Oracle Tuxedo ATMI Application Using C