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diff --git a/tcl/docs/lock.html b/tcl/docs/lock.html deleted file mode 100644 index abd15c2..0000000 --- a/tcl/docs/lock.html +++ /dev/null @@ -1,206 +0,0 @@ -<!--Copyright 1999-2009 Oracle. All rights reserved.--> -<html> -<head> - <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> - <meta name="GENERATOR" content="Mozilla/4.75 [en] (X11; U; Linux 2.2.16-22 i686) [Netscape]"> -</head> -<body> - -<h2> -<a NAME="Locking Commands"></a>Locking Commands</h2> -Most locking commands work with the environment handle. However, -when a user gets a lock we create a new lock handle that they then use -with in a similar manner to all the other handles to release the lock. -We present the general locking functions first, and then those that manipulate -locks. -<p><b>> <env> lock_detect [default|oldest|youngest|random]</b> -<p>This command runs the deadlock detector. It directly translates -to the <a href="../../docs/api_c/lock_detect.html">lock_detect</a> DB call. -It returns either a 0 (for success), a DB error message or it throws a -Tcl error with a system message. The first argument sets the policy -for deadlock as follows: -<ul> -<li> -<b>default</b> selects the DB_LOCK_DEFAULT policy for default detection -(default if not specified)</li> - -<li> -<b>oldest </b>selects DB_LOCK_OLDEST to abort the oldest locker on a deadlock</li> - -<li> -<b>random</b> selects DB_LOCK_RANDOM to abort a random locker on a deadlock</li> - -<li> -<b>youngest</b> selects DB_LOCK_YOUNGEST to abort the youngest locker on -a deadlock</li> -</ul> - -<hr WIDTH="100%"> -<br><b>> <env> lock_stat</b> -<p>This command returns a list of name/value pairs where the names correspond -to the C-structure field names of DB_LOCK_STAT and the values are the data -returned. This command is a direct translation of the <a href="../../docs/api_c/lock_stat.html">lock_stat</a> -DB call. -<hr WIDTH="100%"> -<br><a NAME="> <env> lock_id"></a><b>> <env> lock_id</b> -<p>This command returns a unique locker ID value. It directly translates -to the <a href="../../docs/api_c/lock_id.html">lock_id</a> DB call. -<br> -<hr WIDTH="100%"> -<br><a NAME="> <env> lock_id"></a><b>> <env> lock_id_free </b><i>locker</i> -<p>This command frees the locker allockated by the lock_id call. It directly -translates to the <a href="../../docs/api_c/lock_id.html">lock_id_free -</a>DB -call. -<hr WIDTH="100%"> -<br><a NAME="> <env> lock_id"></a><b>> <env> lock_id_set </b><i>current -max</i> -<p>This is a diagnostic command to set the locker id that will get -allocated next and the maximum id that -<br>will trigger the id reclaim algorithm. -<hr WIDTH="100%"> -<br><a NAME="> <env> lock_get"></a><b>> <env> lock_get [-nowait]<i>lockmode -locker obj</i></b> -<p>This command gets a lock. It will invoke the <a href="../../docs/api_c/lock_get.html">lock_get</a> -function. After it successfully gets a handle to a lock, we bind -it to a new Tcl command of the form <b><i>$env.lockX</i></b>, where X is -an integer starting at 0 (e.g. <b>$env.lock0, $env.lock1, </b>etc). -We use the <i>Tcl_CreateObjCommand()</i> to create the top level locking -command function. It is through this handle that the user can release -the lock. Internally, the handle we get back from DB will be stored -as the <i>ClientData</i> portion of the new command set so that future -locking calls will have that handle readily available. -<p>The arguments are: -<ul> -<li> -<b><i>locker</i></b> specifies the locker ID returned from the <a href="#> <env> lock_id">lock_id</a> -command</li> - -<li> -<b><i>obj</i></b> specifies an object to lock</li> - -<li> -the <b><i>lock mode</i></b> is specified as one of the following:</li> - -<ul> -<li> -<b>ng </b>specifies DB_LOCK_NG for not granted (always 0)</li> - -<li> -<b>read</b> specifies DB_LOCK_READ for a read (shared) lock</li> - -<li> -<b>write</b> specifies DB_LOCK_WRITE for an exclusive write lock</li> - -<li> -<b>iwrite </b>specifies DB_LOCK_IWRITE for intent for exclusive write lock</li> - -<li> -<b>iread </b>specifies DB_LOCK_IREAD for intent for shared read lock</li> - -<li> -<b>iwr </b>specifies DB_LOCK_IWR for intent for eread and write lock</li> -</ul> - -<li> -<b>-nowait</b> selects the DB_LOCK_NOWAIT to indicate that we do not want -to wait on the lock</li> -</ul> - -<hr WIDTH="100%"> -<br><b>> <lock> put</b> -<p>This command releases the lock referenced by the command. It is -a direct translation of the <a href="../../docs/api_c/lock_put.html">lock_put</a> -function. It returns either a 0 (for success), a DB error message -or it throws a Tcl error with a system message. Additionally, since -the handle is no longer valid, we will call -<i>Tcl_DeleteCommand() -</i>so -that further uses of the handle will be dealt with properly by Tcl itself. -<br> -<hr WIDTH="100%"> -<br><a NAME="> <env> lock_vec"></a><b>> <env> lock_vec [-nowait] <i>locker -</i>{get|put|put_all|put_obj -[<i>obj</i>] [<i>lockmode</i>] [<i>lock</i>]} ...</b> -<p>This command performs a series of lock calls. It is a direct translation -of the <a href="../../docs/api_c/lock_vec.html">lock_vec</a> function. -This command will return a list of the return values from each operation -specified in the argument list. For the 'put' operations the entry -in the return value list is either a 0 (for success) or an error. -For the 'get' operation, the entry is the lock widget handle, <b>$env.lockN</b> -(as described above in <a href="#> <env> lock_get"><env> lock_get</a>) -or an error. If an error occurs, the return list will contain the -return values for all the successful operations up the erroneous one and -the error code for that operation. Subsequent operations will be -ignored. -<p>As for the other operations, if we are doing a 'get' we will create -the commands and if we are doing a 'put' we will have to delete the commands. -Additionally, we will have to do this after the call to the DB lock_vec -and iterate over the results, creating and/or deleting Tcl commands. -It is possible that we may return a lock widget from a get operation that -is considered invalid, if, for instance, there was a <b>put_all</b> operation -performed later in the vector of operations. The arguments are: -<ul> -<li> -<b><i>locker</i></b> specifies the locker ID returned from the <a href="#> <env> lock_id">lock_id</a> -command</li> - -<li> -<b>-nowait</b> selects the DB_LOCK_NOWAIT to indicate that we do not want -to wait on the lock</li> - -<li> -the lock vectors are tuple consisting of {an operation, lock object, lock -mode, lock handle} where what is required is based on the operation desired:</li> - -<ul> -<li> -<b>get</b> specifes DB_LOCK_GET to get a lock. Requires a tuple <b>{get -<i>objmode</i>} -</b>where -<b><i>mode</i></b> -is:</li> - -<ul> -<li> -<b>ng </b>specifies DB_LOCK_NG for not granted (always 0)</li> - -<li> -<b>read</b> specifies DB_LOCK_READ for a read (shared) lock</li> - -<li> -<b>write</b> specifies DB_LOCK_WRITE for an exclusive write lock</li> - -<li> -<b>iwrite </b>specifies DB_LOCK_IWRITE for intent for exclusive write lock</li> - -<li> -<b>iread </b>specifies DB_LOCK_IREAD for intent for shared read lock</li> - -<li> -<b>iwr </b>specifies DB_LOCK_IWR for intent for eread and write lock</li> -</ul> - -<li> -<b>put</b> specifies DB_LOCK_PUT to release a <b><i>lock</i></b>. -Requires a tuple <b>{put <i>lock}</i></b></li> - -<li> -<b>put_all </b>specifies DB_LOCK_PUT_ALL to release all locks held by <b><i>locker</i></b>. -Requires a tuple <b>{put_all}</b></li> - -<li> -<b>put_obj</b> specifies DB_LOCK_PUT_OBJ to release all locks held by <b><i>locker</i></b> -associated with the given <b><i>obj</i></b>. Requires a tuple <b>{put_obj -<i>obj}</i></b></li> -</ul> -</ul> - -<hr WIDTH="100%"> -<br><a NAME="> <env> lock_vec"></a><b>> <env> lock_timeout <i>timeout</i></b> -<p>This command sets the lock timeout for all future locks in this environment. -The timeout is in micorseconds. -<br> -<br> -</body> -</html> |