DCE Application Programming Guide

Application Programming With NonStop DCE
Threads
HP NonStop DCE Application Programming Guide—429551-003
3-12
NonStop DCE Jacket Routines
DCE_ENDTRANSACTION()
DCE_RESUMETRANSACTION()
The syntax and semantics of these function calls are the same as those of the similarly
named TMF calls.
When using TMF transaction jackets:
•
The transaction_tag parameter of the DCE_BEGINTRANSACTION() function
is not optional.
•
Each thread can have at most one current transaction. A call to the Guardian
RESUMETRANSACTION procedure is automatically performed during thread
dispatch to ensure that the correct transaction context is maintained.
•
Each transaction is initially associated with only the thread that created it by calling
the DCE_BEGINTRANSACTION() function.
•
Another thread can be associated with a specific transaction by using the
DCE_RESUMETRANSACTION() function and specifying the transaction_tag
value returned by the initial DCE_BEGINTRANSACTION() function call.
•
If a thread is created, it does not inherit its parent's transaction; the created
thread's transaction context is nil.
•
If a thread terminates or is destroyed while it has an active transaction, that
transaction is then inaccessible from the process. Use exception handlers for
pthread_cancel_e if cancellation is a possibility. Alternatively, use the
pthread_cleanup_push() and pthread_cleanup_pop() functions to ensure
that the transaction is terminated if the thread exits or is canceled.
•
If a transaction is aborted by an operator, network partition, or another process, an
error is reported when the initiating thread attempts to operate on the transaction.
•
A process using TMF transaction demarcation jackets must not call:
°
The TMF procedures BEGINTRANSACTION, ABORTTRANSACTION,
ENDTRANSACTION, and RESUMETRANSACTION
°
The SQL/MP BEGIN-WORK and COMMIT-WORK procedures
•
A SERVERCLASS_SEND_ operation propagates the current thread’s transaction
to the receiving Pathway server. RPCs do not propagate a transaction to a DCE
server.
•
A process can perform a maximum of 100 concurrent transactions. If this
maximum is exceeded, a call to the DCE_BEGINTRANSACTION() function fails,
returning error number 83 (too many transactions).
Appendix C, NonStop DCE Jacket Functions, contains reference information for TMF
transaction jackets.