wmic useraccount SID blank spaces/empty lines

Question

I have this two commands to get SID useraccount

wmic useraccount where name='%username%' get sid | findstr /b /C:"S-1" > file.txt

or

for /F "tokens=2 delims=," %f in ('whoami /user /FO CSV /NH') do echo %~f > file.txt

both cases (file.txt) contain blank spaces/empty lines. I try to remove with

findstr /r /v "^$"

But it is impossible. How can remove all blank spaces/empty lines to get only SID number

Answer 1

@echo off
    setlocal enableextensions disabledelayedexpansion

    for /f "skip=2 tokens=2 delims=," %%a in ('
        wmic  path win32_useraccount 
        where name^="%username%" 
        get   sid^,status /format:csv
    ') do (
        >"file.txt" <nul set /p"=%%a"
    )

That will skip headers, include an additional field so the sid is the second field in the record (in csv format the node field gets included) so we can avoid an ending carriage return in the output of the wmic command (each line ends in CR+CR+LF) and the output is sent to the file using a set /p command with the input stream reading from nul device. This way the output to the file will not include the ending CR+LF that is included with echo

The same code for in the whoami version

@echo off
    setlocal enableextensions disabledelayedexpansion

    for /f "tokens=2 delims=," %%a in ('
        whoami /user /FO CSV /NH
    ') do (
        >"file.txt" <nul set /p"=%%~a"
    )