Why my .bat script doesn't delete the files when the total count reaches 8 in the folder?

setlocal EnableDelayedExpansion

pushd C:\backups
set top=7
set filespec=*.bak
set counter=0

for /f "delims=" %%f in ('dir /b %filespec%') do (
    set /a counter+=1
    if !counter! GTR %top% del /q "%%f"
)

I have .bak files, if the number of backup files gets more than 7 i.e. 8 then delete the oldest one.

for example

 1. bak1.bak      10:01 am
 2. bak2.bak      10:02 am
 3. bak3.bak      10:03 am
 4. bak4.bak      10:04 am
 5. bak5.bak      10:05 am
 6. bak6.bak      10:06 am
 7. bak7.bak      10:07 am
 8. bak8.bak      10:08 am

now, the script shall delete then bak1.bak which was taken at 10:01 hence oldest.

Making it

 1. bak2.bak      10:02 am
 2. bak3.bak      10:03 am
 3. bak4.bak      10:04 am
 4. bak5.bak      10:05 am
 5. bak6.bak      10:06 am
 6. bak7.bak      10:07 am
 7. bak8.bak      10:08 am

so if again a file is added i.e.

bak9.bak 10:09

then delete the oldest one i.e. bak2.bak

I wrote the script to but it doesn’t exactly work that way. What it does is that it only keeps the top 7 records even if the number of files are more than 8 e.g. rightnow i have 13 files and if i run it it will keep only top 7 and rest 6 would be deleted but this needs to happen only if the number of files gets 8 and hence deleting the oldest one hence making them 7 again.

>Solution :

Right now, you aren’t listing the files by age, you’re listing them alphabetically by filename. In order to list the files by age, you need to use the /o:-d option of dir in order to sort them from newest to oldest.

@echo off
setlocal EnableDelayedExpansion

pushd "C:\backups"
set "top=7"
set "filespec=*.bak"
set "counter=0"

for /f "delims=" %%f in ('dir /b /o:-d %filespec%') do (
    set /a counter+=1
    if !counter! GTR %top% del /q "%%~f"
)