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DB_ENV-&gt;txn_recover
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<pre>
#include &lt;db.h&gt;

int
DB_ENV-&gt;txn_recover(DB_ENV *dbenv, DB_PREPLIST preplist[],
 long count, long *retp, u_int32_t flags);
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Description: DB_ENV-&gt;txn_recover
Database environment recovery restores transactions that were prepared,
but not yet resolved at the time of the system shut down or crash, to
their state prior to the shut down or crash, including any locks
previously held. The DB_ENV-&gt;txn_recover method returns a list of those
prepared transactions.
The DB_ENV-&gt;txn_recover method should only be called after the environment has
been recovered.
Multiple threads of control may call DB_ENV-&gt;txn_recover, but only one
thread of control may resolve each returned transaction, that is, only
one thread of control may call <a href="../../db4-devel-4.7.25/api_c/txn_commit.html">DB_TXN-&gt;commit</a> or <a href="../../db4-devel-4.7.25/api_c/txn_abort.html">DB_TXN-&gt;abort</a>
on each returned transaction. Callers of DB_ENV-&gt;txn_recover must call
<a href="../../db4-devel-4.7.25/api_c/txn_discard.html">DB_TXN-&gt;discard</a> to discard each transaction they do not resolve.
On return from DB_ENV-&gt;txn_recover, the preplist parameter will
be filled in with a list of transactions that must be resolved by the
application (committed, aborted or discarded). The preplist
parameter is a structure of type DB_PREPLIST; the following DB_PREPLIST
fields will be filled in:
 
DB_TXN * txn;<ul compact><li>The transaction handle for the transaction.</ul>
u_int8_t gid[DB_XIDDATASIZE];<ul compact><li>The global transaction ID for the transaction. The global transaction
ID is the one specified when the transaction was prepared. The
application is responsible for ensuring uniqueness among global
transaction IDs.</ul>
 
The DB_ENV-&gt;txn_recover method
returns a non-zero error value on failure
and 0 on success.

Parameters 
 count<ul compact><li>The count parameter specifies the number of available entries
in the passed-in preplist array. The retp parameter
returns the number of entries DB_ENV-&gt;txn_recover has filled in, in the
array.</ul>
 flags<ul compact><li>The flags parameter must be set to one of the following values:
 
<a name="DB_FIRST">DB_FIRST</a><ul compact><li>Begin returning a list of prepared, but not yet resolved transactions.
Specifying this flag begins a new pass over all prepared, but not yet
completed transactions, regardless of whether they have already been returned
in previous calls to DB_ENV-&gt;txn_recover.
Calls to DB_ENV-&gt;txn_recover from different threads of control should not
be intermixed in the same environment.</ul>
<a name="DB_NEXT">DB_NEXT</a><ul compact><li>Continue returning a list of prepared, but not yet resolved transactions,
starting where the last call to DB_ENV-&gt;txn_recover left off.</ul>
 </ul>
 preplist<ul compact><li>The preplist parameter references memory into which
 the list of transactions to be resolved by the application is copied.</ul> 
 
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 Class
<a href="../../db4-devel-4.7.25/api_c/env_class.html">DB_ENV</a>, <a href="../../db4-devel-4.7.25/api_c/txn_class.html">DB_TXN</a>
 See Also
<a href="../../db4-devel-4.7.25/api_c/txn_list.html">Transaction Subsystem and Related Methods</a>
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