RunIndependently (Daemon subroutine): Difference between revisions

From m204wiki
Jump to navigation Jump to search
mNo edit summary
m (→‎Exceptions: remove Sirius Mods version reference)
 
(18 intermediate revisions by 6 users not shown)
Line 1: Line 1:
<span style="font-size:120%"><b>Run specified command(s) in parallel with issuing thread.</b></span>
{{Template:Daemon:RunIndependently subtitle}}
<var>RunIndependently</var> runs on the daemon thread the command or set of commands specified by its first argument. Unlike <var>[[Run_(Daemon_function)|Run]]</var>, this method returns immediately, and the thread issuing <var>RunIndependently</var> can run in parallel with the <var>daemon</var> thread. Unlike <var>[[RunAsynchronously_(Daemon_subroutine)|RunAsynchronously]]</var>, this method makes the <var>daemon</var> thread completely independent of the parent thread, so the output from the commands can never be retrieved.


RunIndependently is a member of the [[Daemon class]]
==Syntax==
{{Template:Daemon:RunIndependently syntax}}


This method runs on the daemon thread the command or set of commands specified by its first argument. Unlike the Run method, this method returns immediately, and the thread issuing the RunIndependently method can run in parallel with the daemon thread. Unlike the [[RunAsynchronously (Daemon function)]], this method makes the daemon thread completely independent of the parent thread, so the output from the commands can never be retrieved.
===Syntax terms===
 
<table class="syntaxTable">
==RunIndependently Syntax==
<tr><th>daemon</th>
<pre>
<td>A previously defined <var>Daemon</var> object. </td></tr>
%daem:RunIndependently(command, [%inputObj])
<tr><th>commands</th>
</pre>
<td>A string or <var>[[Stringlist class|Stringlist]]</var> that is the command or the set of commands executed by the <var>daemon</var>.</td></tr>
 
<tr><th><var>Input</var></th>
===Syntax Terms===
<td>An object passed to the <var class="term">daemon</var> object. This optional, [[Notation conventions for methods#Named parameters|name allowed]], argument is passed by deep copy and not by reference, so <var class="term">object</var> must be deep copyable, as described in [[Copying objects|"Copying objects"]].</td></tr>
<dl>
</table>
<dt>%daem
<dd>A previously defined Daemon object.  
<dt>command
<dd>A string or Stringlist that is the required command or the set of commands executed by the daemon.  
<dt>%inputObj
<dd>The object passed to the daemon method object. This optional argument is passed by deep copy and not by reference, so '''%inputObj''' must be deep copyable, as described in [[Copying objects]].
</dl>


==Exceptions==
==Exceptions==
<var>RunIndependently</var> can throw the following exception:<dl>
   
   
This subroutine can throw the following exceptions:<dl>
<dt><var>[[DaemonLost_class|DaemonLost]]</var>
<dd>If the <var>daemon</var> object is lost (probably restarted), a <var>DaemonLost</var> exception is thrown. Since <var>RunIndependently</var> does not wait for the <var>daemon</var> thread to do anything, a <var>DaemonLost</var> exception indicates that the <var>daemon</var> thread was lost <b><i>before</i></b> <var>RunIndependently</var> was invoked.  
<dt>DaemonLost  
<dd>If the daemon object is lost (probably restarted), a DaemonLost exception is thrown. Since RunIndependently does not wait for the daemon thread to do anything, a DaemonLost exception indicates that the daemon thread was lost '''before''' the RunIndependently method was invoked. This exception will only be thrown in ''[[Sirius Mods]]'' Version 7.2 and later.
</dl>
</dl>


==Usage Notes==
==Usage notes==
<ul>
<ul>
<li>Issuing <var>RunIndependently</var> against a [[Daemon class#Transactional daemons|transactional daemon]] results in request cancellation.  
<li>RunIndependently was introduced in ''[[Sirius Mods]]'' Version 7.0.
<li>If the <var class="term">daemon</var> thread and its daemons hold record locks that conflict with the parent thread's family (excluding the <var class="term">daemon</var> thread itself and its daemons), <var>RunIndependently</var> results in request cancellation.
<li>Issuing RunIndependently against a transactional daemon results in request cancellation.  
<li><var>RunIndependently</var> is the rough <var>Daemon</var> class equivalent of the <var>[[$CommBg|$CommBg]]</var> function.  
<li>If the daemon thread and its daemons hold record locks that conflict with the parent thread's family (excluding the daemon thread and its daemons), RunIndependently results in request cancellation.  
<li>After a <var>RunIndependently</var> method, the <var class="term">daemon</var> object is set to null. This is because the <var class="term">daemon</var> thread runs completely independently of the parent thread once a <var>RunIndependently</var> method is invoked, so there is nothing useful the parent thread can do with such a daemon, anyway.
<li>This is an example RunIndependently call:
<li>The passing of objects and commands to daemons is identical whether the method is <var>[[Run_(Daemon_function)|Run]]</var> or <var>RunIndependently</var> &mdash; see [[Daemon class#Working with Daemon objects|"Working with Daemon objects"]] for more information about passing commands and objects to a daemon.  
 
<pre>
%daem:runIndependently(%list2, %x)
</pre>
<li>The RunIndependently method is the rough Daemon class equivalent of the $commbg function.  
<li>After a RunIndependently method, the daemon object is set to null. This is because the daemon thread runs completely independently of the parent thread once a RunIndependently method is invoked, so there is nothing useful the parent thread can do with such a daemon object, anyway.  
<li>Even if the parent thread of an independently running daemon logs off, the daemon thread can continue to run.  
<li>Even if the parent thread of an independently running daemon logs off, the daemon thread can continue to run.  
<li>No daemon class mechanism is provided for a parent thread to retrieve the output from an independently running daemon.  
<li>No <var>Daemon</var> class mechanism is provided for a parent thread to retrieve the output from an independently running <var>Daemon</var>.
<li>As described in [[Daemon class]], RunIndependently's Stringlist argument can pass multiple commands to the daemon.  
<li>As described in [[Daemon class#Working with Daemon objects|"Working with Daemon objects"]], the <var>RunIndependently</var> <var class="term">commands</var> argument can pass multiple commands to the <var class="term">daemon</var> method object.  
<li>See [[Daemon class]] for more information about passing commands and objects to a daemon -- the passing of objects and commands to daemons is identical whether the method is Run or RunIndependently.
<li>For more information about independent daemons, see [[Daemon class#Asynchronous and Independent daemons|"Asynchronous and Independent daemons"]].
</ul>
</ul>


[[Category:Daemon methods|RunIndependently]]
==Examples==
[[Category:System methods]]
<p class="code">%daem:runIndependently(%list2, %x)
</p>
 
==See also==
{{Template:Daemon:RunIndependently footer}}

Latest revision as of 16:33, 27 August 2018

Run commands on an independent Daemon thread (Daemon class)

RunIndependently runs on the daemon thread the command or set of commands specified by its first argument. Unlike Run, this method returns immediately, and the thread issuing RunIndependently can run in parallel with the daemon thread. Unlike RunAsynchronously, this method makes the daemon thread completely independent of the parent thread, so the output from the commands can never be retrieved.

Syntax

daemon:RunIndependently( commands, [[Input=] object]) Throws DaemonLost, IncorrectDaemonState

Syntax terms

daemon A previously defined Daemon object.
commands A string or Stringlist that is the command or the set of commands executed by the daemon.
Input An object passed to the daemon object. This optional, name allowed, argument is passed by deep copy and not by reference, so object must be deep copyable, as described in "Copying objects".

Exceptions

RunIndependently can throw the following exception:

DaemonLost
If the daemon object is lost (probably restarted), a DaemonLost exception is thrown. Since RunIndependently does not wait for the daemon thread to do anything, a DaemonLost exception indicates that the daemon thread was lost before RunIndependently was invoked.

Usage notes

  • Issuing RunIndependently against a transactional daemon results in request cancellation.
  • If the daemon thread and its daemons hold record locks that conflict with the parent thread's family (excluding the daemon thread itself and its daemons), RunIndependently results in request cancellation.
  • RunIndependently is the rough Daemon class equivalent of the $CommBg function.
  • After a RunIndependently method, the daemon object is set to null. This is because the daemon thread runs completely independently of the parent thread once a RunIndependently method is invoked, so there is nothing useful the parent thread can do with such a daemon, anyway.
  • The passing of objects and commands to daemons is identical whether the method is Run or RunIndependently — see "Working with Daemon objects" for more information about passing commands and objects to a daemon.
  • Even if the parent thread of an independently running daemon logs off, the daemon thread can continue to run.
  • No Daemon class mechanism is provided for a parent thread to retrieve the output from an independently running Daemon.
  • As described in "Working with Daemon objects", the RunIndependently commands argument can pass multiple commands to the daemon method object.
  • For more information about independent daemons, see "Asynchronous and Independent daemons".

Examples

%daem:runIndependently(%list2, %x)

See also

Retrieved from "https://m204wiki.rocketsoftware.com/index.php?title=RunIndependently_(Daemon_subroutine)&oldid=116751"