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diff --git a/bdb/docs/ref/transapp/env_open.html b/bdb/docs/ref/transapp/env_open.html deleted file mode 100644 index 7209a3fef5f..00000000000 --- a/bdb/docs/ref/transapp/env_open.html +++ /dev/null @@ -1,174 +0,0 @@ -<!--$Id: env_open.so,v 1.1 2000/07/25 17:56:36 bostic Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB Reference Guide: Opening the environment</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> -<table><tr valign=top> -<td><h3><dl><dt>Berkeley DB Reference Guide:<dd>Transaction Protected Applications</dl></h3></td> -<td width="1%"><a href="../../ref/transapp/app.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/transapp/data_open.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p> -<h1 align=center>Opening the environment</h1> -<p>Creating transaction-protected applications using the Berkeley DB library is -quite easy. Applications first use <a href="../../api_c/env_open.html">DBENV->open</a> to initialize -the database environment. Transaction-protected applications normally -require all four Berkeley DB subsystems, so the <a href="../../api_c/env_open.html#DB_INIT_MPOOL">DB_INIT_MPOOL</a>, -<a href="../../api_c/env_open.html#DB_INIT_LOCK">DB_INIT_LOCK</a>, <a href="../../api_c/env_open.html#DB_INIT_LOG">DB_INIT_LOG</a> and <a href="../../api_c/env_open.html#DB_INIT_TXN">DB_INIT_TXN</a> flags -should be specified. -<p>Once the application has called <a href="../../api_c/env_open.html">DBENV->open</a>, it opens its -databases within the environment. Once the databases are opened, the -application makes changes to the databases inside of transactions. Each -set of changes that entail a unit of work should be surrounded by the -appropriate <a href="../../api_c/txn_begin.html">txn_begin</a>, <a href="../../api_c/txn_commit.html">txn_commit</a> and <a href="../../api_c/txn_abort.html">txn_abort</a> -calls. The Berkeley DB access methods will make the appropriate calls into -the lock, log and memory pool subsystems in order to guarantee -transaction semantics. When the application is ready to exit, all -outstanding transactions should have been committed or aborted. -<p>Databases accessed by a transaction must not be closed during the -transaction. Once all outstanding transactions are finished, all open -Berkeley DB files should be closed. When the Berkeley DB database files have been -closed, the environment should be closed by calling <a href="../../api_c/env_close.html">DBENV->close</a>. -<p>The following code fragment creates the database environment directory, -then opens the environment, running recovery. Our DB_ENV -database environment handle is declared to be free-threaded using the -<a href="../../api_c/env_open.html#DB_THREAD">DB_THREAD</a> flag, and so may be used by any number of threads that -we may subsequently create. -<p><blockquote><pre>#include <sys/types.h> -#include <sys/stat.h> -<p> -#include <errno.h> -#include <pthread.h> -#include <stdarg.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> -<p> -#include <db.h> -<p> -#define ENV_DIRECTORY "TXNAPP" -<p> -void env_dir_create(void); -void env_open(DB_ENV **); -<p> -int -main(int argc, char *argv) -{ - extern char *optarg; - extern int optind; - DB *db_cats, *db_color, *db_fruit; - DB_ENV *dbenv; - pthread_t ptid; - int ch; -<p> - while ((ch = getopt(argc, argv, "")) != EOF) - switch (ch) { - case '?': - default: - usage(); - } - argc -= optind; - argv += optind; -<p> - env_dir_create(); - env_open(&dbenv); -<p> - return (0); -} -<p> -void -env_dir_create() -{ - struct stat sb; -<p> - /* - * If the directory exists, we're done. We do not further check - * the type of the file, DB will fail appropriately if it's the - * wrong type. - */ - if (stat(ENV_DIRECTORY, &sb) == 0) - return; -<p> - /* Create the directory, read/write/access owner only. */ - if (mkdir(ENV_DIRECTORY, S_IRWXU) != 0) { - fprintf(stderr, - "txnapp: mkdir: %s: %s\n", ENV_DIRECTORY, strerror(errno)); - exit (1); - } -} -<p> -void -env_open(DB_ENV **dbenvp) -{ - DB_ENV *dbenv; - int ret; -<p> - /* Create the environment handle. */ - if ((ret = db_env_create(&dbenv, 0)) != 0) { - fprintf(stderr, - "txnapp: db_env_create: %s\n", db_strerror(ret)); - exit (1); - } -<p> - /* Set up error handling. */ - dbenv->set_errpfx(dbenv, "txnapp"); -<p> - /* - * Open a transactional environment: - * create if it doesn't exist - * free-threaded handle - * run recovery - * read/write owner only - */ - if ((ret = dbenv->open(dbenv, ENV_DIRECTORY, - DB_CREATE | DB_INIT_LOCK | DB_INIT_LOG | - DB_INIT_MPOOL | DB_INIT_TXN | DB_RECOVER | DB_THREAD, - S_IRUSR | S_IWUSR)) != 0) { - dbenv->err(dbenv, ret, "dbenv->open: %s", ENV_DIRECTORY); - exit (1); - } -<p> - *dbenvp = dbenv; -}</pre></blockquote> -<p>After running this initial program, we can use the <a href="../../utility/db_stat.html">db_stat</a> -utility to display the contents of the environment directory: -<p><blockquote><pre>prompt> db_stat -e -h TXNAPP -3.2.1 Environment version. -120897 Magic number. -0 Panic value. -1 References. -6 Locks granted without waiting. -0 Locks granted after waiting. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= -Mpool Region: 4. -264KB Size (270336 bytes). --1 Segment ID. -1 Locks granted without waiting. -0 Locks granted after waiting. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= -Log Region: 3. -96KB Size (98304 bytes). --1 Segment ID. -3 Locks granted without waiting. -0 Locks granted after waiting. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= -Lock Region: 2. -240KB Size (245760 bytes). --1 Segment ID. -1 Locks granted without waiting. -0 Locks granted after waiting. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= -Txn Region: 5. -8KB Size (8192 bytes). --1 Segment ID. -1 Locks granted without waiting. -0 Locks granted after waiting.</pre></blockquote> -<table><tr><td><br></td><td width="1%"><a href="../../ref/transapp/app.html"><img src="../../images/prev.gif" alt="Prev"></a><a href="../../ref/toc.html"><img src="../../images/ref.gif" alt="Ref"></a><a href="../../ref/transapp/data_open.html"><img src="../../images/next.gif" alt="Next"></a> -</td></tr></table> -<p><font size=1><a href="http://www.sleepycat.com">Copyright Sleepycat Software</a></font> -</body> -</html> |