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The 48 syntax of the entry in that file is a single line with the string 49 "set_flags", one or more whitespace characters, and the method flag 50 parameter as a string; for example, "set_flags DB_TXN_NOSYNC". Because 51 the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 52 file is read when the database environment is opened, it will silently 53 overrule configuration done before that time. 54 </p> 55 <p> 56 The <code class="methodname">DB_ENV->set_flags()</code> <span> 57 <span> 58 method returns a non-zero error value on failure and 0 on success. 59 </span> 60 61 </span> 62 </p> 63 <div class="sect2" lang="en" xml:lang="en"> 64 <div class="titlepage"> 65 <div> 66 <div> 67 <h3 class="title"><a id="id1669076"></a>Parameters</h3> 68 </div> 69 </div> 70 </div> 71 <div class="sect3" lang="en" xml:lang="en"> 72 <div class="titlepage"> 73 <div> 74 <div> 75 <h4 class="title"><a id="id1669188"></a>flags</h4> 76 </div> 77 </div> 78 </div> 79 <p> 80 The <span class="bold"><strong>flags</strong></span> parameter must be set by 81 bitwise inclusively <span class="bold"><strong>OR</strong></span>'ing together 82 one or more of the following values: 83 </p> 84 <div class="itemizedlist"> 85 <ul type="disc"> 86 <li> 87 <p><a id="envset_flags_DB_AUTO_COMMIT"></a> 88 <code class="literal">DB_AUTO_COMMIT</code> 89 </p> 90 <p> 91 If set, <a class="link" href="db.html" title="Chapter��2.�� The DB Handle">DB</a> handle 92 operations for which no explicit transaction handle was specified, and 93 which modify databases in the database environment, will be 94 automatically enclosed within a transaction. 95 </p> 96 <p> 97 Calling <code class="methodname">DB_ENV->set_flags()</code> with this flag only affects the specified 98 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handle (and any other 99 Berkeley DB handles opened within the scope of that handle). For 100 consistent behavior across the environment, all 101 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in the 102 environment must either set this flag 103 or the flag should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 104 configuration file. 105 </p> 106 <p> 107 This flag may be used to configure Berkeley DB at any time during the life 108 of the application. 109 </p> 110 </li> 111 <li> 112 <p><a id="set_flags_DB_CDB_ALLDB"></a> 113 <code class="literal">DB_CDB_ALLDB</code> 114 </p> 115 <p> 116 If set, Berkeley DB Concurrent Data Store applications will perform 117 locking on an environment-wide basis rather than on a per-database 118 basis. 119 </p> 120 <p> 121 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_CDB_ALLDB flag only affects 122 the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 123 handle (and any other Berkeley DB handles opened within the scope of 124 that handle). For consistent behavior across the environment, all 125 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in 126 the environment must either set the DB_CDB_ALLDB flag or the flag 127 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 128 configuration file. 129 </p> 130 <p> 131 The DB_CDB_ALLDB flag may be used to configure Berkeley DB only before 132 the <a class="xref" href="envopen.html" title="DB_ENV->open()">DB_ENV->open()</a> method 133 is called. 134 </p> 135 </li> 136 <li> 137 <p><a id="set_flags_DB_DIRECT_DB"></a> 138 <code class="literal">DB_DIRECT_DB</code> 139 </p> 140 <p> 141 Turn off system buffering of Berkeley DB database files to avoid 142 double caching. 143 </p> 144 <p> 145 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_DIRECT_DB flag only affects 146 the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 147 handle (and any other Berkeley DB handles opened within the scope of 148 that handle). For consistent behavior across the environment, all 149 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in 150 the environment must either set the DB_DIRECT_DB flag or the flag 151 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 152 configuration file. 153 </p> 154 <p> 155 The DB_DIRECT_DB flag may be used to configure Berkeley DB at any time 156 during the life of the application. 157 </p> 158 </li> 159 <li> 160 <p><a id="set_flags_DB_DSYNC_DB"></a> 161 <code class="literal">DB_DSYNC_DB</code> 162 </p> 163 <p> 164 Configure Berkeley DB to flush database writes to the backing disk 165 before returning from the write system call, rather than flushing 166 database writes explicitly in a separate system call, as necessary. 167 This is only available on some systems (for example, systems 168 supporting the IEEE/ANSI Std 1003.1 (POSIX) standard O_DSYNC flag, or 169 systems supporting the Windows FILE_FLAG_WRITE_THROUGH flag). This 170 flag may result in inaccurate file modification times and other 171 file-level information for Berkeley DB database files. This flag will 172 almost certainly result in a performance decrease on most systems. 173 This flag is only applicable to certain filesysystems (for example, the 174 Veritas VxFS filesystem), where the filesystem's support for trickling 175 writes back to stable storage behaves badly (or more likely, has been 176 misconfigured). 177 </p> 178 <p> 179 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_DSYNC_DB flag only affects 180 the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 181 handle (and any other Berkeley DB handles opened within the scope of 182 that handle). For consistent behavior across the environment, all 183 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in 184 the environment must either set the DB_DSYNC_DB flag or the flag 185 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 186 configuration file. 187 </p> 188 <p> 189 The DB_DSYNC_DB flag may be used to configure Berkeley DB at any time 190 during the life of the application. 191 </p> 192 </li> 193 <li> 194 <p><a id="set_flags_DB_MULTIVERSION"></a> 195 <code class="literal">DB_MULTIVERSION</code> 196 </p> 197 <p> 198 If set, all databases in the environment will be opened as if 199 DB_MULTIVERSION is passed to the <a class="xref" href="dbopen.html" title="DB->open()">DB->open()</a> 200 method. This flag will be ignored for queue databases for which DB_MULTIVERSION is not 201 supported. 202 </p> 203 <p> 204 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_MULTIVERSION flag only 205 affects the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handle (and any other 206 Berkeley DB handles opened within the scope of that handle). For 207 consistent behavior across the environment, all <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 208 handles opened in the environment must either set the DB_MULTIVERSION flag or the flag 209 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 210 configuration file. 211 </p> 212 <p> 213 The DB_MULTIVERSION flag may be used to configure Berkeley DB at any 214 time during the life of the application. 215 </p> 216 </li> 217 <li> 218 <p><a id="set_flags_DB_NOLOCKING"></a> 219 <code class="literal">DB_NOLOCKING</code> 220 </p> 221 <p> 222 If set, Berkeley DB will grant all requested mutual exclusion mutexes 223 and database locks without regard for their actual availability. This 224 functionality should never be used for purposes other than debugging. 225 </p> 226 <p> 227 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_NOLOCKING flag only affects 228 the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 229 handle (and any other Berkeley DB handles opened within the scope of 230 that handle). 231 </p> 232 <p> 233 The DB_NOLOCKING flag may be used to configure Berkeley DB at any time 234 during the life of the application. 235 </p> 236 </li> 237 <li> 238 <p><a id="set_flags_DB_NOMMAP"></a> 239 <code class="literal">DB_NOMMAP</code> 240 </p> 241 <p> 242 If set, Berkeley DB will copy read-only database files into the local 243 cache instead of potentially mapping them into process memory (see the 244 description of the <a class="xref" href="envset_mp_mmapsize.html" title="DB_ENV->set_mp_mmapsize()">DB_ENV->set_mp_mmapsize()</a> 245 method for further information). 246 </p> 247 <p> 248 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_NOMMAP flag only affects the 249 specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handle 250 (and any other Berkeley DB handles opened within the scope of that 251 handle). For consistent behavior across the environment, all 252 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in the 253 environment must either set the DB_NOMMAP flag or the flag should be 254 specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 255 configuration file. 256 </p> 257 <p> 258 The DB_NOMMAP flag may be used to configure Berkeley DB at any time 259 during the life of the application. 260 </p> 261 </li> 262 <li> 263 <p><a id="set_flags_DB_NOPANIC"></a> 264 <code class="literal">DB_NOPANIC</code> 265 </p> 266 <p> 267 If set, Berkeley DB will ignore any panic state in the database 268 environment. (Database environments in a panic state normally refuse 269 all attempts to call Berkeley DB functions, returning <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_RUNRECOVERY" class="olink">DB_RUNRECOVERY</a>.) 270 This functionality should never be used for purposes other than 271 debugging. 272 </p> 273 <p> 274 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_NOPANIC flag only affects the 275 specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handle 276 (and any other Berkeley DB handles opened within the scope of that 277 handle). 278 </p> 279 <p> 280 The DB_NOPANIC flag may be used to configure Berkeley DB at any time 281 during the life of the application. 282 </p> 283 </li> 284 <li> 285 <p><a id="set_flags_DB_OVERWRITE"></a> 286 <code class="literal">DB_OVERWRITE</code> 287 </p> 288 <p> 289 Overwrite files stored in encrypted formats before deleting them. 290 Berkeley DB overwrites files using alternating 0xff, 0x00 and 0xff 291 byte patterns. For file overwriting to be effective, the underlying 292 file must be stored on a fixed-block filesystem. Systems with 293 journaling or logging filesystems will require operating system 294 support and probably modification of the Berkeley DB sources. 295 </p> 296 <p> 297 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_OVERWRITE flag only affects 298 the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 299 handle (and any other Berkeley DB handles opened within the scope of 300 that handle). 301 </p> 302 <p> 303 The DB_OVERWRITE flag may be used to configure Berkeley DB at any time 304 during the life of the application. 305 </p> 306 </li> 307 <li> 308 <p><a id="set_flags_DB_PANIC_ENVIRONMENT"></a> 309 <code class="literal">DB_PANIC_ENVIRONMENT</code> 310 </p> 311 <p> 312 If set, Berkeley DB will set the panic state for the database 313 environment. (Database environments in a panic state normally refuse 314 all attempts to call Berkeley DB functions, returning <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_RUNRECOVERY" class="olink">DB_RUNRECOVERY</a>.) 315 This flag may not be specified using the environment's <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> file. 316 </p> 317 <p> 318 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_PANIC_ENVIRONMENT flag 319 affects the database environment, including all threads of control 320 accessing the database environment. 321 </p> 322 <p> 323 The DB_PANIC_ENVIRONMENT flag may be used to configure Berkeley DB 324 only after the <a class="xref" href="envopen.html" title="DB_ENV->open()">DB_ENV->open()</a> method is called. 325 </p> 326 </li> 327 <li> 328 <p><a id="set_flags_DB_REGION_INIT"></a> 329 <code class="literal">DB_REGION_INIT</code> 330 </p> 331 <p> 332 In some applications, the expense of page-faulting the underlying 333 shared memory regions can affect performance. (For example, if the 334 page-fault occurs while holding a lock, other lock requests can 335 convoy, and overall throughput may decrease.) If set, Berkeley DB 336 will page-fault shared regions into memory when initially creating or 337 joining a Berkeley DB environment. In addition, Berkeley DB will 338 write the shared regions when creating an environment, forcing the 339 underlying virtual memory and filesystems to instantiate both the 340 necessary memory and the necessary disk space. This can also avoid 341 out-of-disk space failures later on. 342 </p> 343 <p> 344 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_REGION_INIT flag only affects 345 the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 346 handle (and any other Berkeley DB handles opened within the scope of 347 that handle). For consistent behavior across the environment, all 348 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in 349 the environment must either set the DB_REGION_INIT flag or the flag 350 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 351 configuration file. 352 </p> 353 <p> 354 The DB_REGION_INIT flag may be used to configure Berkeley DB at any 355 time during the life of the application. 356 </p> 357 </li> 358 <li> 359 <p><a id="envset_flags_DB_TIME_NOTGRANTED"></a> 360 <code class="literal">DB_TIME_NOTGRANTED</code> 361 </p> 362 <p> 363 If set, database calls timing out based on lock or transaction timeout 364 values will return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_LOCK_NOTGRANTED" class="olink">DB_LOCK_NOTGRANTED</a> 365 instead of <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_LOCK_DEADLOCK" class="olink">DB_LOCK_DEADLOCK</a>. 366 This allows applications to distinguish between operations which have 367 deadlocked and operations which have exceeded their time limits. 368 </p> 369 <p> 370 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_TIME_NOTGRANTED flag only 371 affects the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handle (and any other 372 Berkeley DB handles opened within the scope of that handle). For 373 consistent behavior across the environment, all 374 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in the 375 environment must either set the DB_TIME_NOTGRANTED flag or the flag 376 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 377 configuration file. 378 </p> 379 <p> 380 The <code class="literal">DB_TIME_NOTGRANTED</code> flag may be used to configure Berkeley DB at 381 any time during the life of the application. 382 </p> 383 <p> 384 Note that the <a class="xref" href="lockget.html" title="DB_ENV->lock_get()">DB_ENV->lock_get()</a> 385 and <a class="xref" href="lockvec.html" title="DB_ENV->lock_vec()">DB_ENV->lock_vec()</a> 386 methods are unaffected by this flag. 387 </p> 388 </li> 389 <li> 390 <p><a id="envset_flags_DB_TXN_NOSYNC"></a> 391 <code class="literal">DB_TXN_NOSYNC</code> 392 </p> 393 <p> 394 If set, Berkeley DB will not write or synchronously flush the log on 395 transaction commit. This means that transactions exhibit the ACI 396 (atomicity, consistency, and isolation) properties, but not D 397 (durability); that is, database integrity will be maintained, but if 398 the application or system fails, it is possible some number of the 399 most recently committed transactions may be undone during recovery. 400 The number of transactions at risk is governed by how many log updates 401 can fit into the log buffer, how often the operating system flushes 402 dirty buffers to disk, and how often the log is checkpointed. 403 </p> 404 <p> 405 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_TXN_NOSYNC flag only affects 406 the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 407 handle (and any other Berkeley DB handles opened within the scope of 408 that handle). For consistent behavior across the environment, all 409 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in 410 the environment must either set the DB_TXN_NOSYNC flag or the flag 411 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 412 configuration file. 413 </p> 414 <p> 415 The DB_TXN_NOSYNC flag may be used to configure Berkeley DB at any 416 time during the life of the application. 417 </p> 418 </li> 419 <li> 420 <p><a id="set_flags_DB_TXN_NOWAIT"></a> 421 <code class="literal">DB_TXN_NOWAIT</code> 422 </p> 423 <p> 424 If set and a lock is unavailable for any Berkeley DB operation 425 performed in the context of a transaction, cause the operation to 426 return <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_LOCK_DEADLOCK" class="olink">DB_LOCK_DEADLOCK</a> 427 (or <a href="../../programmer_reference/program_errorret.html#program_errorret.DB_LOCK_NOTGRANTED" class="olink">DB_LOCK_NOTGRANTED</a> 428 if configured using the DB_TIME_NOTGRANTED flag). 429 </p> 430 <p> 431 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_TXN_NOWAIT flag only affects 432 the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 433 handle (and any other Berkeley DB handles opened within the scope of 434 that handle). For consistent behavior across the environment, all 435 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in 436 the environment must either set the DB_TXN_NOWAIT flag or the flag 437 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 438 configuration file. 439 </p> 440 <p> 441 The DB_TXN_NOWAIT flag may be used to configure Berkeley DB at any 442 time during the life of the application. 443 </p> 444 </li> 445 <li> 446 <p><a id="set_flags_DB_TXN_SNAPSHOT"></a> 447 <code class="literal">DB_TXN_SNAPSHOT</code> 448 </p> 449 <p> 450 If set, all transactions in the environment will be started as if 451 DB_TXN_SNAPSHOT were passed to the 452 <a class="xref" href="txnbegin.html" title="DB_ENV->txn_begin()">DB_ENV->txn_begin()</a> method, and all 453 non-transactional cursors will be opened as if DB_TXN_SNAPSHOT were 454 passed to the <a class="xref" href="dbcursor.html" title="DB->cursor()">DB->cursor()</a> method. 455 </p> 456 <p> 457 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_TXN_SNAPSHOT flag only 458 affects the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 459 handle (and any other Berkeley DB handles opened within the scope of that handle). For 460 consistent behavior across the environment, all 461 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in the 462 environment must either set the DB_TXN_SNAPSHOT flag or the flag 463 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 464 configuration file. 465 </p> 466 <p> 467 The DB_TXN_SNAPSHOT flag may be used to configure Berkeley DB at any 468 time during the life of the application. 469 </p> 470 </li> 471 <li> 472 <p><a id="set_flags_DB_TXN_WRITE_NOSYNC"></a> 473 <code class="literal">DB_TXN_WRITE_NOSYNC</code> 474 </p> 475 <p> 476 If set, Berkeley DB will write, but will not synchronously flush, the 477 log on transaction commit. This means that transactions exhibit the 478 ACI (atomicity, consistency, and isolation) properties, but not D 479 (durability); that is, database integrity will be maintained, but if 480 the system fails, it is possible some number of the most recently 481 committed transactions may be undone during recovery. The number of 482 transactions at risk is governed by how often the system flushes dirty 483 buffers to disk and how often the log is checkpointed. 484 </p> 485 <p> 486 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_TXN_WRITE_NOSYNC flag only 487 affects the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 488 handle (and any other Berkeley DB handles opened within the scope of that handle). For 489 consistent behavior across the environment, all 490 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in the 491 environment must either set the DB_TXN_WRITE_NOSYNC flag or the flag 492 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 493 configuration file. 494 </p> 495 <p> 496 The DB_TXN_WRITE_NOSYNC flag may be used to configure Berkeley DB at 497 any time during the life of the application. 498 </p> 499 </li> 500 <li> 501 <p><a id="set_flags_DB_YIELDCPU"></a> 502 <code class="literal">DB_YIELDCPU</code> 503 </p> 504 <p> 505 If set, Berkeley DB will yield the processor immediately after each 506 page or mutex acquisition. This functionality should never be used 507 for purposes other than stress testing. 508 </p> 509 <p> 510 Calling <code class="methodname">DB_ENV->set_flags()</code> with the DB_YIELDCPU flag only affects 511 the specified <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 512 handle (and any other Berkeley DB handles opened within the scope of 513 that handle). For consistent behavior across the environment, all 514 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> handles opened in 515 the environment must either set the DB_YIELDCPU flag or the flag 516 should be specified in the <a href="../../programmer_reference/env_db_config.html#env_db_config.DB_CONFIG" class="olink">DB_CONFIG</a> 517 configuration file. 518 </p> 519 <p> 520 The DB_YIELDCPU flag may be used to configure Berkeley DB at any time 521 during the life of the application. 522 </p> 523 </li> 524 </ul> 525 </div> 526 </div> 527 <div class="sect3" lang="en" xml:lang="en"> 528 <div class="titlepage"> 529 <div> 530 <div> 531 <h4 class="title"><a id="id1670622"></a>onoff</h4> 532 </div> 533 </div> 534 </div> 535 <p> 536 If the <span class="bold"><strong>onoff</strong></span> parameter is zero, the 537 specified flags are cleared; otherwise they are set. 538 </p> 539 </div> 540 </div> 541 <div class="sect2" lang="en" xml:lang="en"> 542 <div class="titlepage"> 543 <div> 544 <div> 545 <h3 class="title"><a id="id1669640"></a>Errors</h3> 546 </div> 547 </div> 548 </div> 549 <p> 550 The <code class="methodname">DB_ENV->set_flags()</code> <span> 551 <span> 552 method may fail and return one of the following non-zero errors: 553 </span> 554 555 </span> 556 </p> 557 <div class="sect3" lang="en" xml:lang="en"> 558 <div class="titlepage"> 559 <div> 560 <div> 561 <h4 class="title"><a id="id1670196"></a>EINVAL</h4> 562 </div> 563 </div> 564 </div> 565 <p> 566 An invalid flag value or parameter was specified. 567 </p> 568 </div> 569 </div> 570 <div class="sect2" lang="en" xml:lang="en"> 571 <div class="titlepage"> 572 <div> 573 <div> 574 <h3 class="title"><a id="id1669797"></a>Class</h3> 575 </div> 576 </div> 577 </div> 578 <p> 579 <a class="link" href="env.html" title="Chapter��5.�� The DB_ENV Handle">DB_ENV</a> 580 </p> 581 </div> 582 <div class="sect2" lang="en" xml:lang="en"> 583 <div class="titlepage"> 584 <div> 585 <div> 586 <h3 class="title"><a id="id1669881"></a>See Also</h3> 587 </div> 588 </div> 589 </div> 590 <p> 591 <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a> 592 </p> 593 </div> 594 </div> 595 <div class="navfooter"> 596 <hr /> 597 <table width="100%" summary="Navigation footer"> 598 <tr> 599 <td width="40%" align="left"><a accesskey="p" href="envset_feedback.html">Prev</a>��</td> 600 <td width="20%" align="center"> 601 <a accesskey="u" href="env.html">Up</a> 602 </td> 603 <td width="40%" align="right">��<a accesskey="n" href="envset_intermediate_dir_mode.html">Next</a></td> 604 </tr> 605 <tr> 606 <td width="40%" align="left" valign="top">DB_ENV->set_feedback()��</td> 607 <td width="20%" align="center"> 608 <a accesskey="h" href="index.html">Home</a> 609 </td> 610 <td width="40%" align="right" valign="top">��DB_ENV->set_intermediate_dir_mode()</td> 611 </tr> 612 </table> 613 </div> 614 </body> 615</html> 616