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diff --git a/bdb/docs/api_c/env_open.html b/bdb/docs/api_c/env_open.html deleted file mode 100644 index 677f40c1591..00000000000 --- a/bdb/docs/api_c/env_open.html +++ /dev/null @@ -1,205 +0,0 @@ -<!--$Id: env_open.so,v 10.61 2000/12/01 15:50:31 bostic Exp $--> -<!--Copyright 1997, 1998, 1999, 2000 by Sleepycat Software, Inc.--> -<!--All rights reserved.--> -<html> -<head> -<title>Berkeley DB: DBENV->open</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>DBENV->open</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 -DBENV->open(DB_ENV *, char *db_home, u_int32_t flags, int mode); -</pre></h3> -<h1>Description</h1> -<p>The DBENV->open function is the interface for opening the Berkeley DB -environment. It provides a structure for creating a consistent -environment for processes using one or more of the features of Berkeley DB. -<p>The <b>db_home</b> argument to DBENV->open (and file name -resolution in general) is described in -<a href="../ref/env/naming.html">Berkeley DB File Naming</a>. -<p>The <b>flags</b> argument specifies the subsystems that are initialized -and how the application's environment affects Berkeley DB file naming, among -other things. -<p>The <b>flags</b> value must be set to 0 or by bitwise inclusively <b>OR</b>'ing together one or more -of the following values. -<p>As there are a large number of flags that can be specified, they have been -grouped together by functionality. The first group of flags indicate -which of the Berkeley DB subsystems should be initialized: -<p><dl compact> -<p><dt><a name="DB_JOINENV">DB_JOINENV</a><dd>Join an existing environment. This option allows applications to -join an existing environment without knowing which Berkeley DB subsystems -the environment supports. -<p><dt><a name="DB_INIT_CDB">DB_INIT_CDB</a><dd>Initialize locking for the <a href="../ref/cam/intro.html">Berkeley DB Concurrent Data Store</a> -product. In this mode, Berkeley DB provides multiple reader/single writer -access. The only other subsystem that should be specified with the -DB_INIT_CDB flag is DB_INIT_MPOOL. -<p>Access method calls are largely unchanged when using this flag, although -any cursors through which update operations (e.g., <a href="../api_c/dbc_put.html">DBcursor->c_put</a>, -<a href="../api_c/dbc_del.html">DBcursor->c_del</a>) will be made must have the <a href="../api_c/db_cursor.html#DB_WRITECURSOR">DB_WRITECURSOR</a> value -set in the flags parameter to the cursor call that creates the cursor. -See <a href="../api_c/db_cursor.html">DB->cursor</a> for more information. -<p><dt><a name="DB_INIT_LOCK">DB_INIT_LOCK</a><dd>Initialize the locking subsystem. This subsystem should be used when -multiple processes or threads are going to be reading and writing a Berkeley DB -database, so that they do not interfere with each other. If all threads -are accessing the database(s) read-only, then locking is unnecessary. -When the DB_INIT_LOCK flag is specified, it is usually necessary to run -the deadlock detector, as well. See <a href="../utility/db_deadlock.html">db_deadlock</a> and -<a href="../api_c/lock_detect.html">lock_detect</a> for more information. -<p><dt><a name="DB_INIT_LOG">DB_INIT_LOG</a><dd>Initialize the logging subsystem. This subsystem is used when recovery -from application or system failure is necessary. -<p>The log is stored in one or more files in the environment directory. -Each file is named using the format <i>log.NNNNNNNNNN</i>, where -<i>NNNNNNNNNN</i> is the sequence number of the file within the log. -For further information, see -<a href="../ref/log/limits.html">Log File Limits</a>. -<p>If the log region is being created and log files are already present, the -log files are reviewed and subsequent log writes are appended -to the end of the log, rather than overwriting current log entries. -<p><dt><a name="DB_INIT_MPOOL">DB_INIT_MPOOL</a><dd>Initialize the shared memory buffer pool subsystem. This subsystem is -used whenever the application is using any Berkeley DB access method. -<p><dt><a name="DB_INIT_TXN">DB_INIT_TXN</a><dd>Initialize the transaction subsystem. This subsystem is used when -recovery and atomicity of multiple operations and recovery are important. -The DB_INIT_TXN flag implies the DB_INIT_LOG flag. -</dl> -<p>The second group of flags govern what recovery, if any, is performed when -the environment is initialized: -<p><dl compact> -<p><dt><a name="DB_RECOVER">DB_RECOVER</a><dd>Run normal recovery on this environment before opening it for normal use. -If this flag is set, the DB_CREATE flag must also be set since the regions -will be removed and recreated. -<p><dt><a name="DB_RECOVER_FATAL">DB_RECOVER_FATAL</a><dd>Run catastrophic recovery on this environment before opening it for normal -use. If this flag is set, the DB_CREATE flag must also be set since the -regions will be removed and recreated. -</dl> -<p>A standard part of the recovery process is to remove the existing Berkeley DB -environment and create a new one in which to perform recovery. If the -thread of control performing recovery does not specify the correct region -initialization information (e.g., the correct memory pool cache size), -the result can be an application running in an environment with incorrect -cache and other subsystem sizes. For this reason, the thread of control -performing recovery should either specify correct configuration -information before calling the DBENV->open function, or it should remove -the environment after recovery is completed, leaving creation of the -correctly sized environment to a subsequent call to DBENV->open. -<p>All Berkeley DB recovery processing must be single-threaded, that is, only a -single thread of control may perform recovery or access a Berkeley DB -environment while recovery is being performed. As it is not an error to -specify DB_RECOVER for an environment for which no recovery is -required, it is reasonable programming practice for the thread of control -responsible for performing recovery and creating the environment to always -specify the DB_RECOVER flag during startup. -<p>The DBENV->open function returns successfully if DB_RECOVER -or DB_RECOVER_FATAL is specified and no log files exist, so it is -necessary to ensure all necessary log files are present before running -recovery. For further information, consult <a href="../utility/db_archive.html">db_archive</a> and -<a href="../utility/db_recover.html">db_recover</a>. -<p>The third group of flags govern file naming extensions in the environment: -<p><dl compact> -<!--$Id: m4.env_flags,v 10.9 2000/06/29 22:54:10 bostic Exp $--> -<p><dt><a name="DB_USE_ENVIRON">DB_USE_ENVIRON</a><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 DB_USE_ENVIRON flag is set. -<p><dt><a name="DB_USE_ENVIRON_ROOT">DB_USE_ENVIRON_ROOT</a><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 DB_USE_ENVIRON_ROOT flag is set, -environment information will be used for file naming only for users with -appropriate permissions (e.g., on UNIX systems, users with a user-ID of 0). -</dl> -<p>Finally, there are a few additional, unrelated flags: -<p><dl compact> -<p><dt><a name="DB_CREATE">DB_CREATE</a><dd>Cause Berkeley DB subsystems to create any underlying files, as necessary. -<p><dt><a name="DB_LOCKDOWN">DB_LOCKDOWN</a><dd>Lock shared Berkeley DB environment files and memory mapped databases into memory. -<p><dt><a name="DB_PRIVATE">DB_PRIVATE</a><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 -DB_PRIVATE flag should not be specified. -<p><dt><a name="DB_SYSTEM_MEM">DB_SYSTEM_MEM</a><dd>Allocate memory from system shared memory instead of from memory backed -by the filesystem. See <a href="../ref/env/region.html">Shared Memory -Regions</a> for more information. -<p><dt><a name="DB_THREAD">DB_THREAD</a><dd>Cause the DB_ENV handle returned by DBENV->open to be -<i>free-threaded</i>, that is, useable by multiple threads within a -single address space. -</dl> -<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>The DBENV->open function returns a non-zero error value on failure and 0 on success. -<h1>Environment Variables</h1> -<p><dl compact> -<p><dt>DB_HOME<dd>The environment variable <b>DB_HOME</b> may be used as the path of -the database home as described in -<a href="../ref/env/naming.html">Berkeley DB File Naming</a>. -</dl> -<h1>Errors</h1> -<p>The DBENV->open function may fail and return a non-zero error for the following conditions: -<p><dl compact> -<p><dt>EAGAIN<dd>The shared memory region was locked and (repeatedly) unavailable. -</dl> -<p><dl compact> -<p><dt>EINVAL<dd>An invalid flag value or parameter was specified. -<p> -The DB_THREAD flag was specified and spinlocks are not -implemented for this architecture. -<p>The DB_HOME or TMPDIR environment variables were set but empty. -<p>An incorrectly formatted <b>NAME VALUE</b> entry or line was found. -</dl> -<p><dl compact> -<p><dt>ENOSPC<dd>HP-UX only: a previously created Berkeley DB environment for this process still -exists. -</dl> -<p>The DBENV->open 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 DBENV->open 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_close.html">DBENV->close</a>, -<a href="../api_c/env_create.html">db_env_create</a>, -<a href="../api_c/env_open.html">DBENV->open</a>, -<a href="../api_c/env_remove.html">DBENV->remove</a>, -<a href="../api_c/db_err.html">DBENV->err</a>, -<a href="../api_c/env_strerror.html">db_strerror</a>, -<a href="../api_c/env_version.html">db_version</a>, -<a href="../api_c/env_set_cachesize.html">DBENV->set_cachesize</a>, -<a href="../api_c/env_set_errcall.html">DBENV->set_errcall</a>, -<a href="../api_c/env_set_errfile.html">DBENV->set_errfile</a>, -<a href="../api_c/env_set_errpfx.html">DBENV->set_errpfx</a>, -<a href="../api_c/env_set_flags.html">DBENV->set_flags</a>, -<a href="../api_c/env_set_mutexlocks.html">DBENV->set_mutexlocks</a>, -<a href="../api_c/env_set_paniccall.html">DBENV->set_paniccall</a>, -and -<a href="../api_c/env_set_verbose.html">DBENV->set_verbose</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> |