For context, I found this among XAMPP batch files:

@echo off 
SetLocal EnableDelayedExpansion
set "PID_LIST="

for /f "tokens=2" %%V in ('tasklist.exe ^| findstr /i "%1" 2^>NUL') do @set "PID_LIST=!PID_LIST! /PID %%V"

if defined PID_LIST (
  taskkill.exe /F %PID_LIST%
) else (
  echo Process %1 not running
)

SetLocal DisableDelayedExpansion
exit

I wish to write a single script to end all tasks related to my webserver. I have a basic understanding of batch, so I have been able to interpret most of what this script does:

1. Delayed expansion is needed for the for loop
2. The for loop gets the second token (PID) from tasklist and saves it into a variable, where the task is given by paramater 1.
3. If the task is found it is ended with taskkill

Based on this I came so far:

@echo off
cd /D %~dp0
for /f "tokens=2" %%V in ('tasklist.exe ^| findstr /i "httpd.exe" 2^>NUL') do taskkill.exe /pid /f %%V
for /f "tokens=2" %%V in ('tasklist.exe ^| findstr /i "mysql" 2^>NUL') do taskkill.exe /pid /f %%V
:: etc

But I would ideally collapse this into one for loop. How could I add or logic to the findstr expression?

I also have a few questions, which I can’t find quick answers to anywhere. Can anyone answer these in the comments?

1. In my script, do I need to EnableDelayedExpansion?
2. What is the purpose of set "PID_LIST=", leaving the variable undefined?
3. I don’t fully understand the command pipe findstr: what is the meaning of 2^>NUL, and why does > need to be careted?
4. How does the set command append to the variable with !VARIABLE!?