How many Bytes?

TechnoMage2021 · May 7, 2023

I've written a batch file that cleans out tons of garbage from my C: drive.
At the start of the batch file is a command that counts the number of files on C:
and after the cleanup, the command runs again to count the number of files left after cleaning.
The two numbers are used to calculate the number of files actually deleted. That works great, but,
I'd also like to know how many megabytes were deleted.
I can do that manually, by just checking the size of the Drive, in "Properties" before and after I run the batch file.
I did that today and it works great. But, it would be even neater if I could incorporate that check for drive size into my batch file.
Is that even possible, using either batch or Powershell language?
Either way, it's beyond my level of expertise. Any help would be greatly appreciated.

cereberus · May 7, 2023

TechnoMage2021 said:
I've written a batch file that cleans out tons of garbage from my C: drive.
At the start of the batch file is a command that counts the number of files on C:
and after the cleanup, the command runs again to count the number of files left after cleaning.
The two numbers are used to calculate the number of files actually deleted. That works great, but,
I'd also like to know how many megabytes were deleted.
I can do that manually, by just checking the size of the Drive, in "Properties" before and after I run the batch file.
I did that today and it works great. But, it would be even neater if I could incorporate that check for drive size into my batch file.
Is that even possible, using either batch or Powershell language?
Either way, it's beyond my level of expertise. Any help would be greatly appreciated.

Use something like

fsutil volume diskFree C:

this tells you free space at beginning

You would probably need to direct output to a text file,

and run command after you haved finished to a second text file.

Then you can read 1st line from each and parse it to set two variables with value before and after.

Then you subtract one from the other.

TechnoMage2021 · May 7, 2023

Thank you, but more steps than I really want.
I'd like some command that would fit inside of my Batch File, and do everything without any action on my part.
That's the beauty of a Batch File, it automates a job, with NO user intervention required.

In reality, the command would have to run twice, once at the start and once more at the end. Just like my file counting command.
On each run, the results would be entered into a variable. At the end, the ending variable would be subtracted from the beginning variable to give me the total Megabytes deleted.

It's not critical for the program to do what it's designed to do. It's just a curiosity for me to get a Byte count.

Someone else had asked me just how many Bytes of HD space my program was freeing up, and I couldn't tell them. I could only get a file count.

I can get a Byte count by just looking at the Properties of C: before and after I run my batch file. But it would just be so neat if I could get my batch file to give me that information.

Topgundcp · May 7, 2023

Copy this line before and after clean in bat file:
for /f "Tokens=2 delims=()" %%a in ('fsutil volume diskfree C: ^| find "Total free bytes"') do echo Before = %%a
Clean up code
for /f "Tokens=2 delims=()" %%a in ('fsutil volume diskfree C: ^| find "Total free bytes"') do echo After = %%a

garlin · May 7, 2023

CMD's "set /a" stops working on any byte counts > 4 GB (2^32).

You have to use PowerShell or another language to subtract the two byte counts. Since I didn't have any actual cleanup functions, cleanup is simulated here by using a fsutil command to create a large file and then delete it.

Code:

@echo off
setlocal EnableDelayedExpansion

REM Simulate cleanup by first creating a large DUMMY FILE
fsutil file createnew test 123456789 > NUL
REM

for /f "Tokens=5 delims=() " %%a in ('fsutil volume diskfree C: ^| find "Total free bytes"') do (
    set bytes=%%a
    set before_bytes=!bytes:,=!
)

REM Free up disk space by removing DUMMY FILE
del test
REM

for /f "Tokens=5 delims=() " %%a in ('fsutil volume diskfree C: ^| find "Total free bytes"') do (
    set bytes=%%a
    set after_bytes=!bytes:,=!
)

REM Number format is padded to 12 digits wide
powershell -nop "$Saved = $env:after_bytes - $env:before_bytes; '{0,12} bytes saved' -f $Saved; '{0,12} GB saved' -f ('{0:N2}' -f ($Saved/1GB))"
endlocal

pparks1 · May 8, 2023

Powerhsell to give you total size and the freespace. This is returning the C drive on my laptop.

Get-WmiObject -Class Win32_LogicalDisk -ComputerName LOCALHOST | ? {$. DriveType -eq 3} | select DeviceID, {[int]($.Size /1MB)}, {[int]($_.FreeSpace /1MB)}

TechnoMage2021 · May 8, 2023

Topgundcp said:
Copy this line before and after clean in bat file:
for /f "Tokens=2 delims=()" %%a in ('fsutil volume diskfree C: ^| find "Total free bytes"') do echo Before = %%a
Clean up code
for /f "Tokens=2 delims=()" %%a in ('fsutil volume diskfree C: ^| find "Total free bytes"') do echo After = %%a

OK, I ran these lines in a Test batch file, with some cleaning lines in between them.
there was no line to subtract the second result from the first result, thus giving me the net gain.
So I suptracted the second result from the first one (pencil & paper) and got a positive .1 GB.
It was showing me more MB of files After Cleaning than Before. Not what I was after!!!
It was actually showing me the increase in Free Space, or my net gain.

Maybe the problem is that the code was showing me Free Space and not occupied space. Eh?
I'm getting more and more certain that was the case, because the numbers I got from those lines of code, were way higher than the amount of data I have on that drive.
On closer examination, I notice the phrase "diskfree"in the code which I'm thinking means Free Space.
So, how can I change that to show Occupied Space and not Free Space?

Each time the count line of code is run, it must place the result into a variable. First time variable A and the second time variable B. Then another line to do the math: Variable A - Variable B = C print C

Something like this from my batch file:

set /a deleted=%Count1% - %Count2%
Echo:
Echo File Count before cleaning: %Count1% files
Echo:
Echo File count after cleaning: %Count2% files
Echo:
Echo Files deleted: %deleted% files

One thing this definitely shows me, is my own lack of programming expertise.

PerpetualCycle · May 8, 2023

Here is how to get it in powershell (I also include formatting to two decimal places) from my nightly run script

Code:

$cdrv = Get-CimInstance -Class Win32_logicaldisk -Filter "DeviceID = 'C:'"
$used = ($cdrv.Size - $cdrv.FreeSpace)/1000000000
$free= $cdrv.Freespace /1000000000
$u=($used).tostring("#.##")
$f=($free).tostring("#.##")
Write-Host C:  $u GB used, $f GB free

Here is the .bat snippet that shows how I run a Daily.ps1 powershell script from batch that will display all the powershell output in log.txt

Code:

@ECHO OFF

(

ECHO.

pwsh -ExecutionPolicy Unrestricted  -NoLogo -NonInteractive -WindowStyle Hidden -File  E:\Gene\Run-Daily\Daily.ps1

) > log.txt 2>&1