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diff --git a/db/docs/api_c/txn_begin.html b/db/docs/api_c/txn_begin.html new file mode 100644 index 000000000..0241d5c1f --- /dev/null +++ b/db/docs/api_c/txn_begin.html @@ -0,0 +1,93 @@ +<!--$Id: txn_begin.so,v 10.37 2001/01/11 17:47:12 bostic Exp $--> +<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> +<!--All rights reserved.--> +<html> +<head> +<title>Berkeley DB: txn_begin</title> +<meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> +<meta name="keywords" content="embedded,database,programmatic,toolkit,b+tree,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,java,C,C++"> +</head> +<body bgcolor=white> + <a name="2"><!--meow--></a> +<table><tr valign=top> +<td> +<h1>txn_begin</h1> +</td> +<td width="1%"> +<a href="../api_c/c_index.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> +</td></tr></table> +<hr size=1 noshade> +<tt> +<h3><pre> +#include <db.h> +<p> +int +txn_begin(DB_ENV *env, + DB_TXN *parent, DB_TXN **tid, u_int32_t flags); +</pre></h3> +<h1>Description</h1> +<p>The txn_begin method creates a new transaction in the environment +and copies a pointer to a DB_TXN that uniquely identifies it into +the memory referenced by <b>tid</b>. +<p>If the <b>parent</b> argument is non-NULL, the new transaction will +be a nested transaction, with the transaction indicated by +<b>parent</b> as its parent. Transactions may be +nested to any level. +<p>The <b>flags</b> parameter must be set to 0 or one of the following +values: +<p><dl compact> +<p><dt><a name="DB_TXN_NOSYNC">DB_TXN_NOSYNC</a><dd>Do not synchronously flush the log when this transaction commits or +prepares. This means the transaction will exhibit the ACI (atomicity, +consistency and isolation) properties, but not D (durability), i.e., +database integrity will be maintained but it is possible that this +transaction may be undone during recovery instead of being redone. +<p>This behavior may be set for an entire Berkeley DB environment as part of the +<a href="../api_c/env_set_flags.html">DBENV->set_flags</a> interface. +<p><dt><a name="DB_TXN_NOWAIT">DB_TXN_NOWAIT</a><dd>If a lock is unavailable for any Berkeley DB operation performed in the context +of this transaction, return immediately instead of blocking on the lock. +The error return in the case will be <a href="../ref/program/errorret.html#DB_LOCK_NOTGRANTED">DB_LOCK_NOTGRANTED</a>. +<p><dt><a name="DB_TXN_SYNC">DB_TXN_SYNC</a><dd>Synchronously flush the log when this transaction commits or prepares. +This means the transaction will exhibit all of the ACID (atomicity, +consistency and isolation and durability) properties. +<p>This behavior is the default for Berkeley DB environments unless the +<a href="../api_c/env_open.html#DB_TXN_NOSYNC">DB_TXN_NOSYNC</a> flag was specified to the <a href="../api_c/env_set_flags.html">DBENV->set_flags</a> +interface. +</dl> +<p><b>Note: An transaction may not span threads, +i.e., each transaction must begin and end in the same thread, and each +transaction may only be used by a single thread.</b> +<p><b>Note: cursors may not span transactions, i.e., each cursor must be opened +and closed within a single transaction.</b> +<p><b>Note: a parent transaction may not issue any Berkeley DB operations, except for +txn_begin, <a href="../api_c/txn_abort.html">txn_abort</a> and <a href="../api_c/txn_commit.html">txn_commit</a>, while it has +active child transactions (child transactions that have not yet been +committed or aborted).</b> +<p>The txn_begin function returns a non-zero error value on failure and 0 on success. +<h1>Errors</h1> +<p>The txn_begin function may fail and return a non-zero error for the following conditions: +<p><dl compact> +<p><dt>ENOMEM<dd>The maximum number of concurrent transactions has been reached. +</dl> +<p>The txn_begin function may fail and return a non-zero error for errors specified for other Berkeley DB and C library or system functions. +If a catastrophic error has occurred, the txn_begin function may fail and return +<a href="../ref/program/errorret.html#DB_RUNRECOVERY">DB_RUNRECOVERY</a>, in which case all subsequent Berkeley DB calls will fail +in the same way. +<h1>See Also</h1> +<a href="../api_c/env_set_tx_max.html">DBENV->set_tx_max</a>, +<a href="../api_c/env_set_tx_recover.html">DBENV->set_tx_recover</a>, +<a href="../api_c/env_set_tx_timestamp.html">DBENV->set_tx_timestamp</a>, +<a href="../api_c/txn_abort.html">txn_abort</a>, +<a href="../api_c/txn_begin.html">txn_begin</a>, +<a href="../api_c/txn_checkpoint.html">txn_checkpoint</a>, +<a href="../api_c/txn_commit.html">txn_commit</a>, +<a href="../api_c/txn_id.html">txn_id</a>, +<a href="../api_c/txn_prepare.html">txn_prepare</a> +and +<a href="../api_c/txn_stat.html">txn_stat</a>. +</tt> +<table><tr><td><br></td><td width="1%"> +<a href="../api_c/c_index.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> +</td></tr></table> +<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> +</body> +</html> |