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Overview

This code snippet shows how a task handler EXE program can be created and registered when the class RScheduler is used to schedule Task Scheduler tasks. The client has to be registered with the scheduler before any tasks can be scheduled. The registration method is called Register() and it takes two parameters, the filename of the program to execute the tasks and the priority which is relative to other clients.

This snippet can be self-signed.

MMP file

The following libraries are required:

LIBRARY             euser.lib
LIBRARY             efsrv.lib
LIBRARY             estor.lib
LIBRARY             schsvr.lib

Source file (ExampleTaskHandler.exe)

#include <schinfo.h>
#include <schtask.h>
#include <s32file.h>
 
static void DoRunTaskL(RFile& aTaskFile)
{
    TInt taskCount(0);
    CFileStore* fileStore;
    RStoreReadStream readStream;
    
    fileStore = CDirectFileStore::FromLC(aTaskFile);
    readStream.OpenLC(*fileStore,fileStore->Root());
 
    //from schtask.h : 
    //The root stream of the direct file store contains a 32-bit value, followed 
    //by the external representations of one or more CScheduledTask objects. The 
    //32-bit value is interpreted as a TInt32 and contains the number of CScheduledTask 
    //objects that follow in the stream.    
    taskCount = readStream.ReadInt32L();
 
    for (TInt index = 0; index < taskCount; index++)
        {
        CScheduledTask* task = CScheduledTask::NewLC(readStream);
        
        // Do something with the task info...           
        //task->Info().iName;
        //task->Info().iTaskId;
        //task->ValidUntil();       
        //HBufC* data = const_cast<HBufC*>(&(task->Data()));
        
        CleanupStack::PopAndDestroy(task);
        }
 
    CleanupStack::PopAndDestroy(2); // fileStore, readStream        
}
 
LOCAL_D TInt RunTask()
{
    TInt err(KErrNoMemory);
    CTrapCleanup* cleanup=CTrapCleanup::New();
    
    if (cleanup)
        {
        RFile file;
        
        //from schtask.h :
        //The registered program can use the RFile::AdoptFromCreator API in conjunction
        //with the APIs provided by this class to access the scheduled task file store
        err = file.AdoptFromCreator(TScheduledTaskFile::FsHandleIndex(),
                                TScheduledTaskFile::FileHandleIndex());                             
        if (err != KErrNone)
            {
            return err;
            }
        
        TRAP(err, DoRunTaskL(file));
            
        file.Close();
        
        delete cleanup;     
        }
    
    return err;
}
 
GLDEF_C TInt E32Main()
{
    return RunTask();
}

Header file

#ifndef __SCHEDULEREXAMPLEAPPUI_H__
#define __SCHEDULEREXAMPLEAPPUI_H__
 
#include <csch_cli.h> // RScheduler
 
class CSchedulerExampleAppUi : public CAknAppUi
    {
    //...
private:
 
    RScheduler iScheduler;
    
    };
    
#endif // __SCHEDULEREXAMPLEAPPUI_H__

Source file

void CSchedulerExampleAppUi::ConstructL()
    {
    //...
    User::LeaveIfError(iScheduler.Connect());
    
    _LIT(KExampleTaskHandlerExe, "ExampleTaskHandler.exe");
    TFileName exampleHandler(KExampleTaskHandlerExe);
        
    User::LeaveIfError(iScheduler.Register(exampleHandler, CActive::EPriorityStandard));    
    }
    
CSchedulerExampleAppUi::~CSchedulerExampleAppUi()
    {
 
    //...    
    iScheduler.Close(); 
    }

Postconditions

The client is registered with the scheduler and ready to schedule Task Scheduler tasks. The program ExampleTaskHandler.exe is responsible for running scheduled tasks.

See also

• CS000987 - Creating persistent and transient schedules with RScheduler
• CS000988 - Creating a condition-based schedule with RScheduler
• CS000989 - Getting schedule and task info using RScheduler
• CS000990 - Getting schedule and task count using RScheduler
• CS000991 - Editing a schedule using RScheduler
• CS000992 - Deleting schedules and tasks using RScheduler