Multithreading - targeting a specific thread of a thread group

function testThrowStart (nThreads)
    variable nThreads
    
    setdatafolder root:
    variable/G threadGrpIDG = ThreadGroupCreate(nThreads)
    variable/G root:numberOfThreads = nThreads
    NVAR threadGrpIDG = root:threadGrpIDG
    variable iThread
    // Make some data specific for each thread and start each thread
    // root:threadDF:threadNum contains number of thread, which matches data passed as paramater in thread Function
    // Threads will get started with the right data becuase each thread waits
    // for a bit after getting its data, see thread function
    for (iThread =0; iThread < nThreads; iThread +=1)
        newdatafolder/o root:threadDF
        variable/G  root:threadDF:threadGrpID =threadGrpIDG
        variable/G root:threadDF:threadNum = iThread
        make/o/n = (100) $"waveA_" + num2str (iThread), $"waveB_" + num2str (iThread), $"waveC_" + num2str (iThread)
        WAVE WaveA = $"waveA_" + num2str (iThread)
        WAVE WAVEB = $"waveB_" + num2str (iThread)
        WAVE WaveC = $"waveC_" + num2str (iThread)
        ThreadStart threadGrpIDG, iThread, testThrowThread (waveA, waveB, waveC)
        ThreadGroupPutDF threadGrpIDG, root:threadDF
    endfor
        
end
 
// calls all the threads nTimes, plays catch with the thread-queue until each thread has its own data
function testThrowRun (nTimes)
    variable nTimes
    
    setdatafolder root:
    NVAR threadGrpIDG = root:threadGrpIDG
    NVAR nThreads = root:numberOfThreads
    variable iThread, iTime
    for (iTime =1; iTime <= nTimes; iTime += 1)
        for (iThread =0; iThread < nThreads; iThread +=1)
            newdatafolder/o root:threadDF
            // data passed to thread is which thread we want to get the data (iThread)
            // and the number of times we have been called (dataVar)
            // when dataVar is 0, the thread will terminate (see testThrowEnd)
            variable/G root:threadDF:threadNum = iThread
            variable/G  root:threadDF:dataVar = iTime
            ThreadGroupPutDF threadGrpIDG, root:threadDF
        endfor
        // Here's we play catch, back and forth till each thread gets its own data
        for (;;)
            // wait for a datafolder from the threads
            DFREF dfr = ThreadGroupGetDFR(threadGrpIDG, 20)
            if (DataFolderRefStatus(dfr ) ==0)
                // if you don't get a datafolder back, everyone is happy
                break
            else
                // take the datafolder, duplicate it, and throw it back on the queue, better luck next time
                DuplicateDataFolder dfr, :notMyFolder
                ThreadGroupPutDF threadGrpIDG, :notMyFolder
                killdatafolder dfr
            endif
        endfor
        sleep/S .1
        doUpdate
    endfor
end
            
// Same strategy as testThrowRun, but passes 0 as dataVar, to signal threads to quit
// then checks that they have quit
function testThrowEnd ()
    
    setdatafolder root:
    NVAR threadGrpIDG = root:threadGrpIDG
    NVAR nThreads = root:numberOfThreads
    variable iThread
    for (iThread =0; iThread < nThreads; iThread +=1)
        newdatafolder/o root:threadDF
        variable/G root:threadDF:threadNum = iThread
        variable/G  root:threadDF:dataVar = 0
        ThreadGroupPutDF threadGrpIDG, root:threadDF
    endfor
     
    for (;;)
        DFREF dfr = ThreadGroupGetDFR(threadGrpIDG, 20)
        if (DataFolderRefStatus(dfr ) ==0)
            break
        else
            DuplicateDataFolder dfr, :notMyFolder
            ThreadGroupPutDF threadGrpIDG, :notMyFolder
            killdatafolder dfr
        endif
    endfor
 
    variable threadsLeft = ThreadGroupWait(threadGrpIDG, 1000)
    if (threadsLeft > 0)
        print "Threads have not ended" 
        variable isReleased = ThreadGroupRelease(threadGrpIDG )
        if (isReleased != 0)
            printf "ThreadGroupRelease returned %d, uh oh.\r", isReleased
        endif
    else
        for (iThread = 0; iThread < nThreads; iThread +=1)
            printf "Thread %d returned %d\r", iThread, ThreadReturnValue(threadGrpIDG, iThread )
        endfor
    endif
end
 
 
ThreadSafe Function testThrowThread (wave1, wave2, wave3)
    WAVE wave1, wave2, wave3
    
    // starter folder tells me who I am
    DFREF dfrInit = ThreadGroupGetDFR(0,inf)
    NVAR myNumber = dfrInit:threadNum
    printf "I am %d.\r", myNumber
    wave1 =0
    wave2 =0
    wave3 =0
    sleep/s .05 // let other thread get their number
    // subsequent folders tell me to process data
    for (;;)
        DFREF dfr = ThreadGroupGetDFR(0,inf)
        NVAR threadNum = dfr:threadNum
        NVAR dataVar = dfr:dataVar
        if (threadNum != myNumber)
            if (!(NVAR_EXISTS (myNumber)))
                print "I don't even know who I am"
            else
                printf "threadNum was %d but I am %d.\r", threadNum, myNumber
                DuplicateDataFolder dfr, :notMyFolder
                ThreadGroupPutDF 0, notMyFolder
            endif
        else
            if (dataVar ==0)
                break
            else
                wave1 +=myNumber + 1
                wave2 +=(myNumber + 1) *2
                wave3 += (myNumber + 1) * 3
            endif
        endif
        killdatafolder dfr
    endfor
    return myNumber
end