New (Daemon constructor): Difference between revisions

From m204wiki
Jump to navigation Jump to search
mNo edit summary
Line 1: Line 1:
{{Template:Daemon:New subtitle}}
{{Template:Daemon:New subtitle}}
<var>New</var> creates a new <var>[[Daemon class|Daemon]]</var> object instance. It has two, optional, arguments.


==Syntax==
==Syntax==
{{Template:Daemon:New syntax}}
{{Template:Daemon:New syntax}}
===Syntax terms===
===Syntax terms===
<table class="syntaxTable">
<table class="syntaxTable">
<tr><th>%daemon</th>
<tr><th>%daemon</th>
<td>A previously defined <var>[[Daemon class|Daemon]]</var> object. </td></tr>
<td>A <var>[[Daemon class|Daemon]]</var> object. </td></tr>
 
<tr><th><var>[%(Daemon):]</var></th>
<tr><th><var>[%(Daemon):]</var></th>
<td>The optional class name in parentheses denotes a <var>[[Notation conventions for methods#Constructors|Constructor]]</var>. See [[#Usage notes|"Usage notes"]], below, for more information about invoking a <var>Daemon</var> <var>Constructor</var>.</td></tr>
<td>The optional class name in parentheses denotes a <var>[[Notation conventions for methods#Constructors|Constructor]]</var>. See [[#Usage notes|"Usage notes"]], below, for more information about invoking a <var>Daemon</var> <var>Constructor</var>.</td></tr>
<tr><th><var>CopyGlobals</var></th>
<tr><th><var>CopyGlobals</var></th>
<td>An optional, [[Methods#Named parameters|name required]] parameter whose value is a <var>[[Boolean enumeration]]</var>.  
<td>An optional, [[Methods#Named parameters|name required]] parameter whose value is a <var>[[Boolean enumeration]]</var>.  
The default is <code>False</code>: do not copy the existing global variable information from the master thread; use default GTBL-creation settings for the daemon.
The default is <code>False</code>: do not copy the existing global variable information from the master thread; use default GTBL-creation settings for the daemon.
If set to <code>True</code>:<ul><li>The GTBL server table is set to the same size on the daemon as it is on the master thread.<li>The GTBLHASH and GTBLPCT parameters on the daemon thread are set to the same values as on the master thread.<li>Only unstructured globals (globals created by $setg or $getg) and Perm Global Images in the master thread GTBL are copied to the daemon (Global Foundsets/Lists, Global Screens, and any Temp Global items are <b><i>not</i></b> copied).</ul></td></tr>
If set to <code>True</code>:
<ul>
<li>The GTBL server table is set to the same size on the daemon as it is on the master thread.
<li>The <var>GTBLHASH</var> and <var>GTBLPCT</var> parameters on the daemon thread are set to the same values as on the master thread.
<li>Only unstructured globals (globals created by <var>[[$Setg]]</var> or <var>[[$Getg]]</var>) and Perm Global Images in the master thread GTBL are copied to the daemon (Global Foundsets/Lists, Global Screens, and any Temp Global items are <b><i>not</i></b> copied).
</ul></td></tr>
 
<tr><th><var>Transactional</var></th>
<tr><th><var>Transactional</var></th>
<td>An optional, name required parameter whose value is a <var>Boolean</var> enumeration.
<td>An optional, name required, parameter whose value is a <var>Boolean</var> enumeration.
<ul><li>If set to <code>True</code>, the daemon is [[Daemon_class#Transactional_daemons|transactional]], with the master and daemon threads share a single updating transaction.<li>If set to <code>False</code>, the default, the daemon is non-transactional.</ul></td></tr>
<ul>
<li>If set to <code>True</code>, the daemon is [[Daemon_class#Transactional_daemons|transactional]], with the master and daemon threads share a single updating transaction.
<li>If set to <code>False</code>, the default, the daemon is non-transactional.
</ul></td></tr>
 
<tr><th><var>OpenAll</var></th>
<tr><th><var>OpenAll</var></th>
<td>An optional, name required parameter whose value is a <var>Boolean</var> enumeration. If set to <code>True</code>, the daemon thread opens all files and groups that are open on the master thread. The files and groups are opened with the same privileges as on the master thread. This parameter is new as of <var class="product">Sirius Mods</var> Version 8.1.</td></tr>
<td>An optional, name required, parameter whose value is a <var>Boolean</var> enumeration. If set to <code>True</code>, the daemon thread opens all files and groups that are open on the master thread. The files and groups are opened with the same privileges as on the master thread. This parameter is new as of <var class="product">Sirius Mods</var> Version 8.1.</td></tr>
</table>
</table>


==Exceptions==
==Exceptions==
This subroutine can throw the following exception:<dl>
This subroutine can throw the following exception:
<dl>
<dt><var>[[NoFreeDaemons_class|NoFreeDaemons]]</var>
<dt><var>[[NoFreeDaemons_class|NoFreeDaemons]]</var>
<dd>If there are no daemon threads available to service the object, a <var>NoFreeDaemons</var> exception is thrown. This exception will only be thrown in <var class="product">[[Sirius Mods|Sirius Mods]]</var> Version 7.2 and later.</dl>
<dd>If there are no daemon threads available to service the object, a <var>NoFreeDaemons</var> exception is thrown. This exception will only be thrown in <var class="product">[[Sirius Mods|Sirius Mods]]</var> Version 7.2 and later.</dl>
Line 28: Line 41:
==Usage notes==
==Usage notes==
<ul>
<ul>
<li>As described in [[Object variables#Using New or other Constructors|"Using New or other Constructors"]], <var>New</var> can be invoked with no object, with an explicit class name, or with an object variable in the class, even if that object is <var>Null</var>:<p class="code">%daemon = new
<li>As described in [[Object variables#Using New or other Constructors|"Using New or other Constructors"]], <var>New</var> can be invoked with no object, with an explicit class name, or with an object variable in the class, even if that object is <var>Null</var>:
<p class="code">%daemon = new


%daemon = %(Daemon):new
%daemon = %(Daemon):new
Line 34: Line 48:
%daemon = %daemon:new
%daemon = %daemon:new
</p>
</p>
<li><var>New</var> not only creates a Daemon object in the user tables, but it also finds a free sdaemon thread and dedicates it to the issuing user. If no sdaemon threads are available, the request is cancelled.</li>
<li><var>New</var> not only creates a <var>Daemon</var> object in the user tables, but it also finds a free sdaemon thread and dedicates it to the issuing user. If no sdaemon threads are available, the request is cancelled.</li>
 
<li>The number of daemons allowed per master thread is limited by the <var>[[MAXDAEM parameter|MAXDAEM]]</var> system parameter, whose default value is 1.</li>
<li>The number of daemons allowed per master thread is limited by the <var>[[MAXDAEM parameter|MAXDAEM]]</var> system parameter, whose default value is 1.</li>
<li>If you specify <code>CopyGlobals=True</code>, and if there is insufficient server space (say, if daemons start out with very big tables, except for GTBL, and the master has a very big GTBL), the daemon fails during initialization.</li>
<li>If you specify <code>CopyGlobals=True</code>, and if there is insufficient server space (say, if daemons start out with very big tables, except for GTBL, and the master has a very big GTBL), the daemon fails during initialization.</li>
<li>Even files opened as part of the subsystem being run by the master thread are opened on a daemon thread when <code>OpenAll=True</code> is specified.</li>
<li>Even files opened as part of the subsystem being run by the master thread are opened on a daemon thread when <code>OpenAll=True</code> is specified.</li>
<li>Opening a lot of files via <code>OpenAll=True</code> is more efficient than opening the files individually with the <code>Open</code> method.</li>
 
<li>If LFTBL on the daemon thread is not enough to allow opening all the groups to be opened by <code>OpenAll=True</code>, the daemon thread issues an error message and logs off, and the <code>New</code> method fails.</li>  
<li>Opening a lot of files via <code>OpenAll=True</code> is more efficient than opening the files individually with the <var>[[Open (Daemon subroutine)|Open]]</var> method.</li>
 
<li>If LFTBL on the daemon thread is not enough to allow opening all the groups to be opened by <code>OpenAll=True</code>, the daemon thread issues an error message and logs off, and the <var>New</var> method fails.</li>  
</ul>
</ul>


==See also==
==See also==
{{Template:Daemon:New footer}}
{{Template:Daemon:New footer}}

Revision as of 02:39, 8 July 2012

Create a new Daemon (Daemon class)


Syntax

%daemon = [%(Daemon):]New[( [CopyGlobals= boolean], [Transactional= boolean], - [OpenAll= boolean])] Throws MaxDaemExceeded, NoFreeDaemons, DaemonLost

Syntax terms

%daemon A Daemon object.
[%(Daemon):] The optional class name in parentheses denotes a Constructor. See "Usage notes", below, for more information about invoking a Daemon Constructor.
CopyGlobals An optional, name required parameter whose value is a Boolean enumeration.

The default is False: do not copy the existing global variable information from the master thread; use default GTBL-creation settings for the daemon. If set to True:

  • The GTBL server table is set to the same size on the daemon as it is on the master thread.
  • The GTBLHASH and GTBLPCT parameters on the daemon thread are set to the same values as on the master thread.
  • Only unstructured globals (globals created by $Setg or $Getg) and Perm Global Images in the master thread GTBL are copied to the daemon (Global Foundsets/Lists, Global Screens, and any Temp Global items are not copied).
Transactional An optional, name required, parameter whose value is a Boolean enumeration.
  • If set to True, the daemon is transactional, with the master and daemon threads share a single updating transaction.
  • If set to False, the default, the daemon is non-transactional.
OpenAll An optional, name required, parameter whose value is a Boolean enumeration. If set to True, the daemon thread opens all files and groups that are open on the master thread. The files and groups are opened with the same privileges as on the master thread. This parameter is new as of Sirius Mods Version 8.1.

Exceptions

This subroutine can throw the following exception:

NoFreeDaemons
If there are no daemon threads available to service the object, a NoFreeDaemons exception is thrown. This exception will only be thrown in Sirius Mods Version 7.2 and later.

Usage notes

  • As described in "Using New or other Constructors", New can be invoked with no object, with an explicit class name, or with an object variable in the class, even if that object is Null:

    %daemon = new %daemon = %(Daemon):new %daemon = %daemon:new

  • New not only creates a Daemon object in the user tables, but it also finds a free sdaemon thread and dedicates it to the issuing user. If no sdaemon threads are available, the request is cancelled.
  • The number of daemons allowed per master thread is limited by the MAXDAEM system parameter, whose default value is 1.
  • If you specify CopyGlobals=True, and if there is insufficient server space (say, if daemons start out with very big tables, except for GTBL, and the master has a very big GTBL), the daemon fails during initialization.
  • Even files opened as part of the subsystem being run by the master thread are opened on a daemon thread when OpenAll=True is specified.
  • Opening a lot of files via OpenAll=True is more efficient than opening the files individually with the Open method.
  • If LFTBL on the daemon thread is not enough to allow opening all the groups to be opened by OpenAll=True, the daemon thread issues an error message and logs off, and the New method fails.

See also

Retrieved from "https://m204wiki.rocketsoftware.com/index.php?title=New_(Daemon_constructor)&oldid=9455"