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diff --git a/bdb/docs/api_tcl/env_open.html b/bdb/docs/api_tcl/env_open.html deleted file mode 100644 index 1c5bafee4b9..00000000000 --- a/bdb/docs/api_tcl/env_open.html +++ /dev/null @@ -1,168 +0,0 @@ -<!--$Id: env_open.so,v 11.21 2000/06/05 15:17:24 sue Exp $--> -<!--$Id: m4.tcl,v 11.17 2000/04/24 17:31:11 sue Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB: berkdb env</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><b>berkdb env</b></h1> -</td> -<td width="1%"> -<a href="../api_tcl/tcl_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>berkdb env - [-cachesize {gbytes bytes ncache}] - [-create] - [-data_dir dirname] - [-errfile filename] - [-home directory] - [-log_dir dirname] - [-mode mode] - [-private] - [-recover] - [-recover_fatal] - [-shm_key shmid] - [-system_mem] - [-tmp_dir dirname] - [-txn [nosync]] - [-txn_max max] - [-use_environ] - [-use_environ_root] -</pre></h3> -<h1>Description</h1> -<p>The <b>berkdb env</b> command opens, and optionally creates, a database -environment. The returned environment handle is bound to a Tcl command -of the form <b>envN</b>, where N is an integer starting at 0 (e.g., env0 -and env1). It is through this Tcl command that the script accesses the -environment methods. -The command automatically initializes the shared memory buffer pool subsystem. -This subsystem is used whenever the application is -using any Berkeley DB access method. -<p>The options are as follows: -<p><dl compact> -<p><dt>-cachesize {gbytes bytes ncache}<dd>Set the size of the database's shared memory buffer pool, i.e., the cache, -to <b>gbytes</b> gigabytes plus <b>bytes</b>. The cache should be the -size of the normal working data set of the application, with some small -amount of additional memory for unusual situations. (Note, the working -set is not the same as the number of simultaneously referenced pages, and -should be quite a bit larger!) -<p>The default cache size is 256KB, and may not be specified as less than -20KB. Any cache size less than 500MB is automatically increased by 25% -to account for buffer pool overhead, cache sizes larger than 500MB are -used as specified. -<p>It is possible to specify caches to Berkeley DB that are large enough so that -they cannot be allocated contiguously on some architectures, e.g., some -releases of Solaris limit the amount of memory that may be allocated -contiguously by a process. If <b>ncache</b> is 0 or 1, the cache will -be allocated contiguously in memory. If it is greater than 1, the cache -will be broken up into <b>ncache</b> equally sized separate pieces of -memory. -<p>For information on tuning the Berkeley DB cache size, see -<a href="../ref/am_conf/cachesize.html">Selecting a cache size</a>. -<p><dt>-create<dd>Cause Berkeley DB subsystems to create any underlying files, as necessary. -<p><dt>-data_dir dirname<dd>Specify the environment's data directory as described in -<a href="../ref/env/naming.html">Berkeley DB File Naming</a>. -<p><dt>-errfile filename<dd> -<p>When an error occurs in the Berkeley DB library, a Berkeley DB error or an error -return value is returned by the function. In some cases, however, the -errno value may be insufficient to completely describe the cause of the -error especially during initial application debugging. -<p>The <b>-errfile</b> argument is used to enhance the mechanism for -reporting error messages to the application by specifying a file to be -used for displaying additional Berkeley DB error messages. In some cases, when -an error occurs, Berkeley DB will output an additional error message to the -specified file reference. -<p>The error message will consist of the environment command name (e.g., env0) -and a colon (":"), an error string, and a trailing <newline> -character. -<p>This error logging enhancement does not slow performance or significantly -increase application size, and may be run during normal operation as well -as during application debugging. -<p><dt>-home directory<dd>The <b>-home</b> argument is described in -<a href="../ref/env/naming.html">Berkeley DB File Naming</a>. -<p><dt>-log_dir dirname<dd>Specify the environment's logging file directory as described in -<a href="../ref/env/naming.html">Berkeley DB File Naming</a>. -<p><dt>-mode mode<dd> -<p>On UNIX systems, or in IEEE/ANSI Std 1003.1 (POSIX) environments, all files created by Berkeley DB -are created with mode <b>mode</b> (as described in <b>chmod</b>(2)) and -modified by the process' umask value at the time of creation (see -<b>umask</b>(2)). The group ownership of created files is based on -the system and directory defaults, and is not further specified by Berkeley DB. -If <b>mode</b> is 0, files are created readable and writeable by both -owner and group. On Windows systems, the mode argument is ignored. -<p><dt>-private<dd>Specify that the environment will only be accessed by a single process -(although that process may be multi-threaded). This flag has two effects -on the Berkeley DB environment. First, all underlying data structures are -allocated from per-process memory instead of from shared memory that is -potentially accessible to more than a single process. Second, mutexes -are only configured to work between threads. -<p>This flag should not be specified if more than a single process is -accessing the environment, as it is likely to cause database corruption -and unpredictable behavior, e.g., if both a server application and the -Berkeley DB utility <a href="../utility/db_stat.html">db_stat</a> will access the environment, the -<b>-private</b> option should not be specified. -<p><dt>-recover<dd>Run normal recovery on this environment before opening it for normal use. -If this flag is set, the <b>-create</b> option must also be set since -the regions will be removed and recreated. -<p><dt>-recover_fatal<dd>Run catastrophic recovery on this environment before opening it for -normal use. If this flag is set, the <b>-create</b> option must also be -set since the regions will be removed and recreated. -<p><dt>-shm_key key<dd>Specify a base segment ID for Berkeley DB environment shared memory regions -created in system memory on systems supporting X/Open-style shared memory -interfaces, e.g., UNIX systems supporting shmget(2) and related System V -IPC interfaces. See <a href="../ref/env/region.html">Shared Memory -Regions</a> for more information. -<p><dt>-system_mem<dd>Allocate memory from system shared memory instead of memory backed by the -filesystem. See <a href="../ref/env/region.html">Shared Memory Regions</a> -for more information. -<p><dt>-tmp_dir dirname<dd>Specify the environment's tmp directory as described in -<a href="../ref/env/naming.html">Berkeley DB File Naming</a>. -<p><dt>-txn [nosync]<dd>Initialize the transaction subsystem. This subsystem is used when -recovery and atomicity of multiple operations and recovery are important. -The <b>-txn</b> option implies the initialization of the logging -and locking subsystems as well. -<p>If the optional <b>nosync</b> argument is specified, the log will not be -synchronously flushed on transaction commit or prepare. This means that -transactions exhibit the ACI (atomicity, consistency and isolation) -properties, but not D (durability), i.e., database integrity will be -maintained but it is possible that some number of the most recently -committed transactions may be undone during recovery instead of being -redone. -<p>The number of transactions that are potentially at risk is governed by -how often the log is checkpointed (see <a href="../utility/db_checkpoint.html">db_checkpoint</a> for more -information) and how many log updates can fit on a single log page. -<p><dt>-txn_max max<dd>Set the maximum number of simultaneous transactions that are supported -by the environment. This bounds the size of backing files. When there -are more than the specified number of concurrent transactions, calls to -<i>env</i> <b>txn</b> will fail (until some active transactions complete). -<p><dt>-use_environ<dd>The Berkeley DB process' environment may be permitted to specify information to -be used when naming files; see <a href="../ref/env/naming.html">Berkeley DB -File Naming</a>. As permitting users to specify which files are used can -create security problems, environment information will be used in file -naming for all users only if the <b>-use_environ</b> flag is set. -<p><dt>-use_environ_root<dd>The Berkeley DB process' environment may be permitted to specify information -to be used when naming files; see <a href="../ref/env/naming.html">Berkeley DB -File Naming</a>. As permitting users to specify which files are used can -create security problems, if the <b>-use_environ_root</b> flag is set, -environment information will be used for file naming only for users with -appropriate permissions (e.g., on IEEE/ANSI Std 1003.1 (POSIX) systems, users with a -user-ID of 0). -</dl> -<p>The <b>berkdb env</b> command returns an environment handle on success. -<p>In the case of error, a Tcl error is thrown. -</tt> -<table><tr><td><br></td><td width="1%"> -<a href="../api_tcl/tcl_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> |