Run (Daemon function)

Run a set of commands on the Daemon thread (Daemon class)

Run is a member of the Daemon class

This callable method runs on the daemon thread the command or set of commands specified by its first argument, and it returns the terminal output from the command(s).

[%strL =] %daem:Run(command, [%inputObj], [%outputObj], -
[Info=%infoObj])

Syntax terms

%strL	If specified, a Stringlist object that contains the terminal output from the command or commands run on the daemon thread.
%daem	A previously defined Daemon object.
command	A string or Stringlist that is the required command or the set of commands executed by the daemon.
%inputObj	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 :hdref refid=copying.. The passed object can be retrieved by the daemon thread using the GetInputObject method (:hdref refid=getinp.).
%outputObj	The object returned from the daemon method object. This optional argument is passed by deep copy and not by reference, so %outputObj must be deep copyable, as described in :hdref refid=copying.. The object set to %outputObj is the object passed by the daemon thread using the ReturnObject method (:hdref refid=retnobj.). Because %outputObj is an output variable, it cannot itself be contained inside an object: that is, it must be a local or a common %variable.
Info=%infoObj	An optional, name required parameter that indicates a second output object returned from the daemon method object. This optional argument is passed by deep copy and not by reference, so %infoObj must be deep copyable, as described in :hdref refid=copying.. The object set to %infoObj is the object passed by the daemon thread using the ReturnInfoObject method (:hdref refid=retnobj.). Because %infoObj is an output variable, it cannot itself be contained inside an object: that is, it must be a local or a common %variable. This parameter is only available in Sirius Mods Version 6.8 and later. For an example of how to use this parameter, see the bottom of the "Usage Notes," below.

Exceptions

This function can throw the following exceptions:

DaemonLost

If the daemon object is lost (probably restarted), a DaemonLost exception is thrown. This exception will only be thrown in Sirius Mods Version 7.2 and later. See (:hdref refid=daemlse.).

Usage notes

• These are example Run calls:

  %strlist = %daem:run('V UTABLE')
  
  %strlist = %daem:run(%list2, %x, %x)
  

• The Run method sets the output object to Null if the daemon command contains no ReturnObject (:hdref refid=retnobj.) invocation. Subsequent master thread references to that object, for example to print it, cancel the request.
• As any Run method input-object argument, an input "parameter object" is passed by deep copy: the parameter object, all objects contained in that object, all objects contained in those objects, and so on are copied and passed to the sdaemon thread. An example of a category of object that may not be passed to a daemon is a Janus Sockets Socket object.
• If a file you want to open on the daemon is already open on the master thread, the Open method (:hdref refid=opndaem.) lets you open the file with the same privileges it had on the master thread.
• As described in :hdref refid=workdae., Run's Stringlist argument can pass multiple commands to the daemon. For example, to pass objects of three different classes, as well as float and longstring values to a daemon request, you can create a user class that contains such objects and the appropriate float and longstring values, then pass a "parameter object" of that class, as follows:

  class Multivar
  public
  variable a is object a
  variable b is object b
  variable c is object c
  variable y is float
  variable z is longstring
  end public
  end class
  ...
  %Multi is object Multivar
  %daem is object daemon
  ...
  %Multi = new
  %Multi:a = %objectA
  %Multi:b = %objectB
  %Multi:c = %objectC
  %Multi:y = 3.1415929
  %Multi:z = %lstrZ
  ...
  %daem:run('I MYPROC', %Multi)
  

  
  

  To make use of the variables passed in the %Multi input parameter above:
  • The file containing MYPROC must be open on the daemon from an invocation of Run with a Model 204 OPEN command argument or from an invocation of the Open method (:hdref refid=opndaem.).
  • The MYPROC procedure must contain an invocation of the GetInputObject method (:hdref refid=getinp.).

  
  

  To return updated values to the master thread above, MYPROC must contain an invocation of ReturnObject (:hdref refid=retnobj.), and the Run method invocation requires an additional argument (represented in the Run method syntax by %inputObject), compatible with the ReturnObject argument. :hdref refid=quickeg. shows the passing of input and output objects between a master and daemon. 
  

• While the optional Info object can be used for any kind of output object, its intent is to separate the "true&CQ. output of a daemon request from informational output (return codes, error messages, diagnostics, etc.). In the following example, a Stringlist object (presumably containing error messages) is used as the Info output:

  %errors is object stringList
  %result is object myClass
  %daem is object daemon
  ...
  %daem:run('MYSUBSYS', , %result, info=%errors)
  

  
  

  The daemon thread running the request returns the Info object using the ReturnInfoObject method (:hdref reftxt=ReturnInfoObject refid=retnobj.):
  

  %errors is object stringList
  ...
  %(daemon):returnInfoObject(%errors)
  

Example

In the following example, a daemon sorts found records, then returns in an object the sorted set of records:

Begin
%FindCriteria is string len 255
%Pazuzu is object Daemon
%Sorted is object SortedRecordset in file MYFILE
%SubList is object stringList
%FindCriteria = 'NICKNAME IS LIKE ''SI*'' '

%SubList = new
Text to %SubList
Begin
%BasicSet is object Recordset in file MYFILE
%Sorted is object SortedRecordset in file MYFILE
%BasicSet = New
Find Records to %BasicSet
{%FindCriteria}
End Find
Sort records in %BasicSet to %Sorted by NICKNAME
%(daemon):returnObject(%Sorted)
End
End Text

%Pazuzu = New
%Pazuzu:run('*LOWER')
%Pazuzu:open('MYFILE')
%Pazuzu:run(%SubList,,%Sorted)

For each record in %Sorted
Print '*'
pai
End For
End

See also

Daemon class	List of Daemon methods	Daemon methods syntax
Notation conventions for methods