How to capture the PID of a process when launching

Question

Is there a way to do this purely in a .bat file?

The purpose is to launch iexplore.exe, then kill just that instance when it's finished.

Answer 1

For some reason your approach of getting process id did not work for me, but since I'm expert in batches, I've coded my own approach, attaching here:

@echo off

call:AsyncCmd
rem call:AsyncCmd "echo hello world"
rem call:AsyncCmd "call build.bat"
exit /b

rem ------------------------------------------------------------------------------------------
rem Starts asynchronous command execution 
rem %1 is command, if empty - only aborts existing build.
rem ------------------------------------------------------------------------------------------
:AsyncCmd
if exist %~dp0SetupBuild_Completed.txt (
    del /f %~dp0SetupBuild_Pid.txt >nul 2>&1
    del /f %~dp0SetupBuild_Completed.txt >nul 2>&1
)

if not exist %~dp0SetupBuild_Pid.txt goto lStartProc
    rem --------------------------------------------------
    rem Abort build process
    rem --------------------------------------------------
    set /p pid=<%~dp0SetupBuild_Pid.txt
    echo Cancelling setup build process, process id %pid%
    pskill -t %pid%
    del /f %~dp0SetupBuild_Pid.txt >nul 2>&1

:lStartProc
if "%~1" == "" exit /b 0

rem --------------------------------------------------
rem Starts asyncronous build process
rem --------------------------------------------------
set dir=%~dp0
set dir=%dir:~0,-1%
for /f "tokens=2 delims==; " %%a in ('wmic process call create "cmd /c mincon.exe && %~1 && echo 1>%~dp0SetupBuild_Completed.txt"^, "%dir%" ^| findstr /r "ProcessId"') do set pid=%%a
echo Setup build started, process id: %pid%
echo %pid%>%~dp0SetupBuild_Pid.txt
exit /b 0

Answer 2

you can use vbscript, here's an example creating notepad, then terminating it using its pid

strComputer = "."
Set objWMIService = GetObject("winmgmts:{impersonationLevel=impersonate}!\\" & strComputer & "\root\cimv2")
Set objStartup = objWMIService.Get("Win32_ProcessStartup")
Set objConfig = objStartup.SpawnInstance_
Set objProcess = GetObject("winmgmts:root\cimv2:Win32_Process")
errReturn = objProcess.Create("notepad.exe", null, objConfig, PID)
If errReturn = 0 Then
    WScript.Echo "Process ID is: " & PID
End If 

WScript.Echo "Ready to kill process: " & PID & "? [Y|y]"
Do While Not WScript.StdIn.AtEndOfLine
   strInput = strInput & WScript.StdIn.Read(1)
Loop
If LCase(strInput) = "y" Then
    WScript.Echo "Select * from Win32_Process Where ProcessId = '" & PID & "'"
    Set colProcessList = objWMIService.ExecQuery("Select * from Win32_Process Where ProcessId = '" & PID & "'")
    For Each objProcess in colProcessList
        objProcess.Terminate()
    Next
End If 

save as myscript.vbs and on command line

c:\test> cscript /nologo myscript.vbs