shell 進程的並行執行

Question

是否有可用於在 Windows 批處理文件中並行執行多個進程的工具？ 我為 Linux（並行和PPSS ）找到了一些有趣的工具，但是，我需要一個用於 Windows 平台的工具。

獎勵：如果該工具還允許以簡單的方式在多台機器之間分配進程，並以PsExec遠程運行進程，那就太好了。

示例：我希望在下面的 for 循環中

for %F in (*.*) do processFile.exe %F

有限數量的 processFile.exe 實例並行運行以利用多核 CPU。

Answer 1

編輯-我修改了腳本以選擇性地顯示每個進程的 output

這是一個本機批處理解決方案，它可靠地並行運行命令列表，一次不會啟動超過n 個進程。

它甚至內置了一種機制，可以通過 PSEXEC 將進程分配到特定的 CPU 或遠程機器，但我還沒有測試過該功能。

完成這項工作的技巧是通過 CMD 進程啟動每個命令，該進程將標准輸出或未定義的句柄重定向到鎖定文件。 該進程將在文件上保持一個排他鎖，直到它終止。 進程如何終止（正常退出、崩潰、終止進程）無關緊要，一旦完成，鎖就會被釋放。

主腳本可以通過嘗試重定向到同一個鎖定文件來測試進程是否仍然處於活動狀態。 如果進程仍然處於活動狀態，則重定向將失敗，如果已終止，則重定向成功。

默認情況下，腳本忽略每個進程的 output。 如果以/O選項作為第一個參數啟動，則它會顯示每個進程的 output，而不會交錯。

我的演示將進程限制設置為 4，並簡單地運行一系列不同長度的 PING 命令。

我已經在 XP、Vista 和 Windows 7 上對此進行了測試。

@echo off
setlocal enableDelayedExpansion

:: Display the output of each process if the /O option is used
:: else ignore the output of each process
if /i "%~1" equ "/O" (
  set "lockHandle=1"
  set "showOutput=1"
) else (
  set "lockHandle=1^>nul 9"
  set "showOutput="
)

:: The list of commands could come from anywhere such as another file
:: or the output of another command. For this demo I will list the
:: commands within this script - Each command is prefixed with :::
::: ping /n 05 ::1
::: ping /n 20 ::1
::: ping /n 10 ::1
::: ping /n 15 ::1
::: ping /n 07 ::1
::: ping /n 05 ::1
::: ping /n 20 ::1
::: ping /n 10 ::1
::: ping /n 15 ::1
::: ping /n 07 ::1

:: Define the maximum number of parallel processes to run.
:: Each process number can optionally be assigned to a particular server
:: and/or cpu via psexec specs (untested).
set "maxProc=4"

:: Optional - Define CPU targets in terms of PSEXEC specs
::           (everything but the command)
::
:: If a CPU is not defined for a proc, then it will be run on the local machine.
:: I haven't tested this feature, but it seems like it should work.
::
:: set cpu1=psexec \\server1 ...
:: set cpu2=psexec \\server1 ...
:: set cpu3=psexec \\server2 ...
:: etc.

:: For this demo force all CPU specs to undefined (local machine)
for /l %%N in (1 1 %maxProc%) do set "cpu%%N="

:: Get a unique base lock name for this particular instantiation.
:: Incorporate a timestamp from WMIC if possible, but don't fail if
:: WMIC not available. Also incorporate a random number.
  set "lock="
  for /f "skip=1 delims=-+ " %%T in ('2^>nul wmic os get localdatetime') do (
    set "lock=%%T"
    goto :break
  )
  :break
  set "lock=%temp%\lock%lock%_%random%_"

:: Initialize the counters
  set /a "startCount=0, endCount=0"

:: Clear any existing end flags
  for /l %%N in (1 1 %maxProc%) do set "endProc%%N="

:: Launch the commands in a loop
:: Modify the IN () clause as needed to retrieve the list of commands
  set launch=1
  for /f "tokens=* delims=:" %%A in ('findstr /b ":::" "%~f0"') do (
    if !startCount! lss %maxProc% (
      set /a "startCount+=1, nextProc=startCount"
    ) else (
      call :wait
    )
    set cmd!nextProc!=%%A
    if defined showOutput echo -------------------------------------------------------------------------------
    echo !time! - proc!nextProc!: starting %%A
    2>nul del %lock%!nextProc!
    %= Redirect the lock handle to the lock file. The CMD process will     =%
    %= maintain an exclusive lock on the lock file until the process ends. =%
    start /b "" cmd /c %lockHandle%^>"%lock%!nextProc!" 2^>^&1 !cpu%%N! %%A
  )
  set "launch="

:wait
:: Wait for procs to finish in a loop
:: If still launching then return as soon as a proc ends
:: else wait for all procs to finish
  :: redirect stderr to null to suppress any error message if redirection
  :: within the loop fails.
  for /l %%N in (1 1 %startCount%) do 2>nul (
    %= Redirect an unused file handle to the lock file. If the process is    =%
    %= still running then redirection will fail and the IF body will not run =%
    if not defined endProc%%N if exist "%lock%%%N" 9>>"%lock%%%N" (
      %= Made it inside the IF body so the process must have finished =%
      if defined showOutput echo ===============================================================================
      echo !time! - proc%%N: finished !cmd%%N!
      if defined showOutput type "%lock%%%N"
      if defined launch (
        set nextProc=%%N
        exit /b
      )
      set /a "endCount+=1, endProc%%N=1"
    )
  )
  if %endCount% lss %startCount% (
    1>nul 2>nul ping /n 2 ::1
    goto :wait
  )

2>nul del %lock%*
if defined showOutput echo ===============================================================================
echo Thats all folks^^!

這是忽略進程 output 的示例運行中的 output

12:24:07.52 - proc1: starting  ping /n 05 ::1
12:24:07.52 - proc2: starting  ping /n 20 ::1
12:24:07.53 - proc3: starting  ping /n 10 ::1
12:24:07.54 - proc4: starting  ping /n 15 ::1
12:24:11.60 - proc1: finished  ping /n 05 ::1
12:24:11.60 - proc1: starting  ping /n 07 ::1
12:24:16.66 - proc3: finished  ping /n 10 ::1
12:24:16.66 - proc3: starting  ping /n 05 ::1
12:24:17.68 - proc1: finished  ping /n 07 ::1
12:24:17.68 - proc1: starting  ping /n 20 ::1
12:24:20.72 - proc3: finished  ping /n 05 ::1
12:24:20.72 - proc3: starting  ping /n 10 ::1
12:24:21.75 - proc4: finished  ping /n 15 ::1
12:24:21.75 - proc4: starting  ping /n 15 ::1
12:24:26.82 - proc2: finished  ping /n 20 ::1
12:24:26.82 - proc2: starting  ping /n 07 ::1
12:24:29.86 - proc3: finished  ping /n 10 ::1
12:24:32.89 - proc2: finished  ping /n 07 ::1
12:24:35.92 - proc4: finished  ping /n 15 ::1
12:24:36.93 - proc1: finished  ping /n 20 ::1
Thats all folks!

這是 output 如果使用顯示進程 output 的/O選項運行

-------------------------------------------------------------------------------
12:24:51.02 - proc1: starting  ping /n 05 ::1
-------------------------------------------------------------------------------
12:24:51.02 - proc2: starting  ping /n 20 ::1
-------------------------------------------------------------------------------
12:24:51.03 - proc3: starting  ping /n 10 ::1
-------------------------------------------------------------------------------
12:24:51.04 - proc4: starting  ping /n 15 ::1
===============================================================================
12:24:55.10 - proc1: finished  ping /n 05 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 5, Received = 5, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
-------------------------------------------------------------------------------
12:24:55.10 - proc1: starting  ping /n 07 ::1
===============================================================================
12:25:00.17 - proc3: finished  ping /n 10 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 10, Received = 10, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
-------------------------------------------------------------------------------
12:25:00.19 - proc3: starting  ping /n 05 ::1
===============================================================================
12:25:01.22 - proc1: finished  ping /n 07 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 7, Received = 7, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
-------------------------------------------------------------------------------
12:25:01.23 - proc1: starting  ping /n 20 ::1
===============================================================================
12:25:04.27 - proc3: finished  ping /n 05 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 5, Received = 5, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
-------------------------------------------------------------------------------
12:25:04.28 - proc3: starting  ping /n 10 ::1
===============================================================================
12:25:05.30 - proc4: finished  ping /n 15 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 15, Received = 15, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
-------------------------------------------------------------------------------
12:25:05.32 - proc4: starting  ping /n 15 ::1
===============================================================================
12:25:10.38 - proc2: finished  ping /n 20 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 20, Received = 20, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
-------------------------------------------------------------------------------
12:25:10.40 - proc2: starting  ping /n 07 ::1
===============================================================================
12:25:13.44 - proc3: finished  ping /n 10 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 10, Received = 10, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
===============================================================================
12:25:16.48 - proc2: finished  ping /n 07 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 7, Received = 7, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
===============================================================================
12:25:19.52 - proc4: finished  ping /n 15 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 15, Received = 15, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
===============================================================================
12:25:20.54 - proc1: finished  ping /n 20 ::1

Pinging ::1 with 32 bytes of data:
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms
Reply from ::1: time<1ms

Ping statistics for ::1:
    Packets: Sent = 20, Received = 20, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms
===============================================================================
Thats all folks!

Answer 2

嘗試start ：

start "title of the process" "P:\ath\to.exe"

它會打開一個具有給定標題的新 window 並執行 BAT、CMD 或 EXE 文件。 您還可以設置優先級，設置相同的環境等。

不可執行的文件用相關程序打開。

進一步閱讀：開始 -> 運行

cmd /k start /?

至少從 WinME 開始就可以使用 Start。

祝你好運！

Answer 3

聽起來您更像是想使用 Powershell 2。但是，您可以使用start生成新cmd windows （或其他進程），另請參見此答案。 盡管您可能必須使用一些其他工具和一些小技巧來創建類似“進程池”的東西（一次最多只能運行n 個實例）。 您可以通過使用tasklist /im並計算已經存在多少（ for循環或wc ，如果適用）並簡單地等待（ ping -n 2::1 >nul 2>&1 ）並再次重新檢查您是否可以產生一個新進程。

我為此拼湊了一個小測試批次：

@echo off
for /l %%i in (1,1,20) do call :loop %%i
goto :eof

:loop
call :checkinstances
if %INSTANCES% LSS 5 (
    rem just a dummy program that waits instead of doing useful stuff
    rem but suffices for now
    echo Starting processing instance for %1
    start /min wait.exe 5 sec
    goto :eof
)
rem wait a second, can be adjusted with -w (-n 2 because the first ping returns immediately;
rem otherwise just use an address that's unused and -n 1)
echo Waiting for instances to close ...
ping -n 2 ::1 >nul 2>&1
rem jump back to see whether we can spawn a new process now
goto loop
goto :eof

:checkinstances
rem this could probably be done better. But INSTANCES should contain the number of running instances afterwards.
for /f "usebackq" %%t in (`tasklist /fo csv /fi "imagename eq wait.exe"^|find /c /v ""`) do set INSTANCES=%%t
goto :eof

它產生最多四個並行執行並最小化的新進程。 等待時間可能需要調整，具體取決於每個進程的執行量和運行時間。 如果您正在做其他事情，您可能還需要調整任務列表正在查找的進程名稱。

但是，無法正確計算該批次產生的進程。 一種方法是在批處理開始時創建一個隨機數（ %RANDOM% ）並創建一個幫助批處理（或生成處理程序），但可以將其 window 標題設置為參數：

@echo off
title %1
"%2" "%3"

這將是一個簡單的批處理，將其標題設置為第一個參數，然后以第三個參數作為參數運行第二個參數。 然后，您可以通過僅選擇具有指定 window 標題（ tasklist /fi "windowtitle eq..." ）的進程來過濾任務列表。 這應該工作相當可靠，並防止太多誤報。 如果您仍有一些實例正在運行，那么搜索cmd.exe將是一個壞主意，因為這會限制您的工作進程池。

您可以使用%NUMBER_OF_PROCESSORS%創建一個合理的默認值來生成多少實例。

您還可以輕松地將其調整為使用psexec遠程生成進程（但由於您必須在另一台機器上擁有管理員權限並在批處理中提供密碼，所以不太可行）。 但是，您必須使用進程名稱進行過濾。

Answer 4

有一個基本的 Windows xargs-like-clone 它支持http://www.pirosa.co.uk/demo/wxargs/wxargs.ZFC35FDC70D2FC69D269EZCA753A8處的 -P 並行處理選項

Answer 5

Linux 下的 GNU xargs 有一個“-P n”開關來並行啟動“n”個進程。

也許 xargs 的 cygwin/mingw 構建也支持這個？

然后你可以使用：

xargs -P 4 processFile < fileList

但是，沒有花哨的多節點進程產生。

Answer 6

我編寫了一個提供多線程支持的庫（以“模擬”線程池行為的方式）

github 上的 MultiBat

這是該庫的內聯版本，但我最好轉到上面的鏈接以獲取最新版本（以及不需要內聯到您的 bat 文件中的版本。

REM ---------------------------------------------------------------------------
REM ---------------------------------------------------------------------------
REM ---------------------------------------------------------------------------
goto:EOF
REM Append this to the END of your batch-file [*.BAT] to get inline "Multi" support

REM  "Multi" is a thread-pool emulation helper library for controlling multi-threaded windows batch [*.BAT] files
REM  Copyright (c) 2020 Adisak Pochanayon
REM  Contact: adisak@gmail.com
REM  See Multi_License.txt for details

REM -----------------------------------

:Multi_Setup

call :Multi_SetName %1

if "%2"=="" (
    if "%NUMBER_OF_PROCESSORS%"=="" call :Multi_SetLimitToMax
) else (
    call :Multi_SetLimit %2
)
goto:EOF

REM -----------------------------------

:Multi_SetName
REM Returns: MULTI_CHILDPROC_WINNAME - name to use for child processes (the window title)

if "%1"=="" (
    SET MULTI_CHILDPROC_WINNAME=Multi-CmdProc
) else (
    SET MULTI_CHILDPROC_WINNAME=Multi-CmdProc-%1
)
goto:EOF

REM -----------------------------------

REM To Enable Hyperthreading, call Multi_SetHyperThread before calling Multi_Setup or Multi_SetLimitToMax

:Multi_SetHyperThread
REM Parameter 1: (optional)
REM        value=1    (or unspecified) - Use Hyperthreading if available
REM        value=0 (or other) - Do not use Hyperthreading to compute the max threads
REM Returns: NumberOfCores - number of real CPU cores
REM Returns: MULTI_HAS_HYPERTHREADING - 1 if the CPU has Hyperthreading
REM Returns: MULTI_USE_HYPERTHREADING - 1 if "Multi" should use Hyperthreading

REM Set variable NumberOfCores
if "%NumberOfCores%"=="" (
    for /f "tokens=*" %%f in ('wmic cpu get NumberOfCores /value ^| find "="') do set %%f
)

REM Set variable MULTI_HAS_HYPERTHREADING
if "%MULTI_HAS_HYPERTHREADING%"=="" (
    if "%NumberOfCores%"=="%NUMBER_OF_PROCESSORS%" (
        REM Non-Hyperthreading
        SET MULTI_HAS_HYPERTHREADING=0
    ) else (
        REM Hyperthreading
        SET MULTI_HAS_HYPERTHREADING=1
    )
}

if "%1"=="" (
    SET MULTI_USE_HYPERTHREADING=%MULTI_HAS_HYPERTHREADING%
) else (
    SET MULTI_USE_HYPERTHREADING=%1
)

REM Set the max threads to the limit (respecting Hyperthreading options)
call :Multi_SetLimitToMax
goto:EOF

REM -----------------------------------

:Multi_SetLimit
REM Parameter 1:
REM        value=N    - Use N as the number of max threads
REM        unspecified - Compute the default number of max threads
REM Returns: MULTI_MAXCHILDREN - the maximum number of child processes to run simultaneously

if "%1"=="" (
    if "%MULTI_MAXCHILDREN%"=="" call :Multi_SetLimitToMax
    goto:EOF
)

SET /A MULTI_MAXCHILDREN=%1
if %MULTI_MAXCHILDREN% LSS 1 SET MULTI_MAXCHILDREN=1
goto:EOF

REM -----------------------------------

:Multi_SetLimitToMax
REM Parameter 1: (optional)
REM        Passed to Multi_SetHyperThread if present
REM Returns: MULTI_MAXCHILDREN - max number of "threads" in pool for "Multi"

if "%1"=="" (
    REM Check if Hyperthreading support was initialized
    if "%NumberOfCores%"=="" (
        call :Multi_SetHyperThread 0
        REM Multi_SetHyperThread calls back to this subroutine so exit to prevent recursion
        goto:EOF
    )
) else (
    call :Multi_SetHyperThread %1
    REM Multi_SetHyperThread calls back to this subroutine so exit to prevent recursion
    goto:EOF
)

if %NUMBER_OF_PROCESSORS% LEQ 3 (
    SET MULTI_MAXCHILDREN=1
) else (
    if "%NumberOfCores%"=="%NUMBER_OF_PROCESSORS%" (
        REM Non-Hyperthreading
        SET /A MULTI_MAXCHILDREN=%NUMBER_OF_PROCESSORS%-2
    ) else if "%MULTI_USE_HYPERTHREADING%"=="1" (
        REM Hyperthreading available and used
        SET /A MULTI_MAXCHILDREN=%NUMBER_OF_PROCESSORS%/2 - 1
    ) else (
        REM Hyperthreading available but not used
        SET /A MULTI_MAXCHILDREN=%NUMBER_OF_PROCESSORS%-2
    )
)
goto:EOF

REM -----------------------------------

:Multi_RunWin

if "%MULTI_CHILDPROC_WINNAME%"=="" call :Multi_SetName

call :Multi_WaitChildrenMax
start "%MULTI_CHILDPROC_WINNAME%" /BELOWNORMAL cmd /c %*
goto:EOF

REM -----------------------------------

:Multi_RunWinMin

if "%MULTI_CHILDPROC_WINNAME%"=="" call :Multi_SetName

call :Multi_WaitChildrenMax
start "%MULTI_CHILDPROC_WINNAME%" /MIN /BELOWNORMAL cmd /c %*
goto:EOF

REM -----------------------------------

:Multi_RunSyncMin

REM Use this command to run things that mess with the window title
REM and otherwise would screw up the "Multi" System
start "Multi-Sync" /MIN /WAIT cmd /c %*
goto:EOF

REM -----------------------------------

:Multi_WaitChildrenMax

REM Wait until less than MULTI_MAXCHILDREN children are running

if "%MULTI_MAXCHILDREN%"=="" call :Multi_SetLimitToMax

call :Multi_WaitChildren %MULTI_MAXCHILDREN%
goto:EOF

REM -----------------------------------

:Multi_WaitChildren

SETLOCAL
REM multi_WAITCOUNT is a local variable
SET multi_WAITCOUNT=1

if "%1"=="" GOTO :loop_WaitChildren
SET /A multi_WAITCOUNT=%1
if %multi_WAITCOUNT% LSS 1 set multi_WAITCOUNT=1

:loop_WaitChildren
call :Multi_GetNumChildren
if %MULTI_NUM_CHILDREN% LSS %multi_WAITCOUNT% GOTO :exit_WaitChildren
timeout /t 1 /nobreak > nul
GOTO :loop_WaitChildren

:exit_WaitChildren
ENDLOCAL
goto:EOF

REM -----------------------------------

:Multi_GetNumChildren
REM Returns: MULTI_NUM_CHILDREN - the number of "children" processes (Windows named MULTI_CHILDPROC_WINNAME)

if "%MULTI_CHILDPROC_WINNAME%"=="" call :Multi_SetName

REM MULTI_NUM_CHILDREN should contain the number of 
REM running %MULTI_CHILDPROC_WINNAME% instances after this
for /f "usebackq" %%t in (`tasklist /fo csv /fi "WINDOWTITLE eq %MULTI_CHILDPROC_WINNAME%" ^| find /c "cmd"`) do (
    SET MULTI_NUM_CHILDREN=%%t
)
goto:EOF

REM -----------------------------------