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/*! @m_page{{c,java},threads,Multithreading}

All WT_CONNECTION methods are thread safe, and WT_CONNECTION handles can
be shared between threads.  Applications typically open a single
connection to each database, per process.  Multi-threaded programs
must wait for all other threads to exit before closing the WT_CONNECTION
handle because that will implicitly close all other handles.
Alternatively, a thread can set an event handler using
WT_CONNECTION::open_session to be notified when a WT_CONNECTION close is
in progress.

WT_SESSION and WT_CURSOR methods are not thread safe and WT_SESSION and
WT_CURSOR handles cannot be accessed concurrently by multiple threads.
Applications typically open one WT_SESSION handle for each thread
accessing a database, and then one or more WT_CURSOR handles within the
session.

WT_SESSION and WT_CURSOR methods may be accessed by different threads
serially (for example, a pool of threads managed by the application with
a set of shared session or cursor handles).  There is no thread-local
state in WiredTiger, and no built-in synchronization of session or
cursor handles, either, so if multiple threads access a session or
cursor handle, access must be serialized by the application.

WT_ASYNC_OP methods are not thread-safe, and must be accessed by only a
single thread at a time.  WT_ASYNC_OP methods may be accessed by
different threads serially (and that is expected to happen when the
asynchronous callback function runs).

@section threads_example Code samples

The code below is taken from the complete example program
@ex_ref{ex_thread.c}.

This is an example of a thread entry point.  A new session is opened for
the thread and used for all operations within that thread.

@snippet ex_thread.c thread scan

Here is the main function that starts the threads.  It opens a single
connection, shared between the threads, and closes the connection after
waiting for all of the threads to exit.

@snippet ex_thread.c thread main

 */