Question

I want to write a batch file that updates a DLL that is in use by a running process, a regular application.

To do this, the plan is to stop the process, copy the DLL to the required location, then restart the process.

I know I can try to kill a process with taskkill. How can I make sure the process has fallen over and died, after I shoot it?

Answer 1

Here’s what I used. It’s a subroutine in a batch file.

set tasklist=%windir%\System32\tasklist.exe
set taskkill=%windir%\System32\taskkill.exe

-------------------------------------------------------
:STOPPROC
    set wasStopped=0
    set procFound=0
    set notFound_result=ERROR:
    set procName=%1
    for /f "usebackq" %%A in (`%taskkill% /IM %procName%`) do (
      if NOT %%A==%notFound_result% (set procFound=1)
    )
    if %procFound%==0 (
      echo The process was not running.
      goto :EOF
    )
    set wasStopped=1
    set ignore_result=INFO:
:CHECKDEAD
    "%windir%\system32\timeout.exe" 3 /NOBREAK
    for /f "usebackq" %%A in (`%tasklist% /nh /fi "imagename eq %procName%"`) do (
      if not %%A==%ignore_result% (goto :CHECKDEAD)
    )
    goto :EOF
-------------------------------------------------------

To use it from within a batch file, do like this:

  call :STOPPROC notepad.exe

Full example:

set tasklist=%windir%\System32\tasklist.exe
set taskkill=%windir%\System32\taskkill.exe

-------------------------------------------------------
:STOPPROC
    set wasStopped=0
    set procFound=0
    set notFound_result=ERROR:
    set procName=%1
    for /f "usebackq" %%A in (`%taskkill% /IM %procName%`) do (
      if NOT %%A==%notFound_result% (set procFound=1)
    )
    if %procFound%==0 (
      echo The process was not running.
      goto :EOF
    )
    set wasStopped=1
    set ignore_result=INFO:
:CHECKDEAD
    "%windir%\system32\timeout.exe" 3 /NOBREAK
    for /f "usebackq" %%A in (`%tasklist% /nh /fi "imagename eq %procName%"`) do (
      if not %%A==%ignore_result% (goto :CHECKDEAD)
    )
    goto :EOF
-------------------------------------------------------

:MAIN 

call :STOPPROC notepad.exe
call :STOPPROC Skype.exe

You’ll notice lines that have all dashes – that’s not a legal syntax for a batch file of course. But, those lines are never reached, because of the use of GOTO statements, so the syntax is never evaluated. Therefore those lines aren’t a problem.