Download Sun Java System Messaging Server 6 2005Q1 MTA Developer`s

Basic Steps to Enqueue Messages
Basic Steps to Enqueue Messages
The basic steps necessary to enqueue one or more messages to the MTA are:
1.
Initialize SDK resources and data structures with mtaInit().
2.
For each message to enqueue, perform the following steps:
a.
Specify the message envelope with mtaEnqueueStart() and
mtaEnqueueTo().
3.
b.
Specify the message header with mtaEnqueueWrite() or
mtaEnqueueWriteLine().
c.
Optionally, if a message body is to be supplied, terminate the message
header and start the message body by writing a blank line to the message
with mtaEnqueueWrite() or mtaEnqueueWriteLine().
d.
Optionally if a message body is to be supplied, write the message body
with mtaEnqueueWrite() or mtaEnqueueWriteLine().
e.
Submit the message with mtaEnqueueFinish().
When you have completed enqueuing messages, deallocate SDK resources and
data structures with mtaDone().
In Step 2e, mtaEnqueueFinish() commits the message to disk. As part of the
enqueue process, the MTA performs any access checks, size checks, format
conversions, address rewritings, and other tasks called for by the site’s MTA
configuration. After these steps are completed and the message has been
successfully written to disk, mtaEnqueueFinish() returns.
Other MTA processes controlled by the MTA Job Controller then begin processing
the new message so as to effect its delivery. In fact, these processes may begin
handling the new message before mtaEnqueueFinish() even returns. As such,
mtaEnqeueueFinish() doesn’t block waiting on these processes; it returns as soon as
all requisite copies of the enqueued message have been safely written to disk. The
subsequent handling of the newly enqueued message is performed by other MTA
processes, and the program which enqueued the message isn’t left waiting for
them.
A message submission can be aborted at any point in Step 2 by calling either
mtaEnqueueFinish() with the MTA_ABORT option specified or mtaDone(). Using the
first method, mtaEnqueueFinish() aborts only the specified message enqueue
context while allowing additional messages to be enqueued. Whereas, mtaDone()
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Messaging Server 6 2005Q1 • MTA Developer’s Reference