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1 files changed, 38 insertions, 24 deletions
diff --git a/docs/programmer_reference/lock_stdmode.html b/docs/programmer_reference/lock_stdmode.html index 243574f9..921405a3 100644 --- a/docs/programmer_reference/lock_stdmode.html +++ b/docs/programmer_reference/lock_stdmode.html @@ -14,7 +14,7 @@ <body> <div xmlns="" class="navheader"> <div class="libver"> - <p>Library Version 11.2.5.3</p> + <p>Library Version 12.1.6.1</p> </div> <table width="100%" summary="Navigation header"> <tr> @@ -22,9 +22,7 @@ </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="lock_max.html">Prev</a> </td> - <th width="60%" align="center">Chapter 16. - The Locking Subsystem - </th> + <th width="60%" align="center">Chapter 16. The Locking Subsystem </th> <td width="20%" align="right"> <a accesskey="n" href="lock_dead.html">Next</a></td> </tr> </table> @@ -38,16 +36,22 @@ </div> </div> </div> - <p>The Berkeley DB locking protocol is described by a conflict matrix. A -conflict matrix is an NxN array in which N is the number of different -lock modes supported, and the (i, j)th entry of the array indicates -whether a lock of mode i conflicts with a lock of mode j. In addition, -Berkeley DB defines the type <span class="bold"><strong>db_lockmode_t</strong></span>, which is the type of a -lock mode within a conflict matrix.</p> - <p>The following is an example of a conflict matrix. The actual conflict -matrix used by Berkeley DB to support the underlying access methods is more -complicated, but this matrix shows the lock mode relationships available -to applications using the Berkeley DB Locking subsystem interfaces directly.</p> + <p> + The Berkeley DB locking protocol is described by a conflict + matrix. A conflict matrix is an NxN array in which N is the + number of different lock modes supported, and the (i, j)th + entry of the array indicates whether a lock of mode i + conflicts with a lock of mode j. In addition, Berkeley DB + defines the type <span class="bold"><strong>db_lockmode_t</strong></span>, + which is the type of a lock mode within a conflict matrix. + </p> + <p> + The following is an example of a conflict matrix. The actual + conflict matrix used by Berkeley DB to support the underlying + access methods is more complicated, but this matrix shows the + lock mode relationships available to applications using the + Berkeley DB Locking subsystem interfaces directly. + </p> <div class="variablelist"> <dl> <dt> @@ -76,10 +80,13 @@ to applications using the Berkeley DB Locking subsystem interfaces directly.</p> <dd>intention to read and write (shared)</dd> </dl> </div> - <p>In a conflict matrix, the rows indicate the lock that is held, and the -columns indicate the lock that is requested. A 1 represents a conflict -(that is, do not grant the lock if the indicated lock is held), and a -0 indicates that it is OK to grant the lock.</p> + <p> + In a conflict matrix, the rows indicate the lock that is + held, and the columns indicate the lock that is requested. A 1 + represents a conflict (that is, do not grant the lock if the + indicated lock is held), and a 0 indicates that it is OK to + grant the lock. + </p> <pre class="programlisting"> Notheld Read Write IWrite IRead IRW Notheld 0 0 0 0 0 0 Read* 0 0 1 1 0 1 @@ -92,14 +99,20 @@ Intent RW 0 1 1 0 0 0</pre> <dt> <span class="term">*</span> </dt> - <dd>In this case, suppose that there is a read lock held on an object. A new -request for a read lock would be granted, but a request for a write lock -would not.</dd> + <dd> + In this case, suppose that there is a read lock + held on an object. A new request for a read lock would + be granted, but a request for a write lock would + not. + </dd> <dt> <span class="term">**</span> </dt> - <dd>In this case, suppose that there is a write lock held on an object. A -new request for either a read or write lock would be denied.</dd> + <dd> + In this case, suppose that there is a write lock + held on an object. A new request for either a read or + write lock would be denied. + </dd> </dl> </div> </div> @@ -114,7 +127,8 @@ new request for either a read or write lock would be denied.</dd> <td width="40%" align="right"> <a accesskey="n" href="lock_dead.html">Next</a></td> </tr> <tr> - <td width="40%" align="left" valign="top">Configuring locking: sizing the system </td> + <td width="40%" align="left" valign="top">Configuring locking: sizing the + system </td> <td width="20%" align="center"> <a accesskey="h" href="index.html">Home</a> </td> |