Out-File not reporting error on failure to write to UNC network path when stream is being repeatedly opened and closed. about powershell HOT 2 OPEN

Could you do a single pipeline rather than continually opening and closing?

Also, does setting $ErrorActionPreference at the root make any difference?

$destfile = "\\UNCSHARE\Folder\Export_Sample_$(get-date -Format "yyyyMMdd_HHmmss").txt"

$srcFile = '\\UNCSHARE\Folder\200MB_Export_20231208_1545.txt'

[int64]$ln = 0
[int64]$SampleCount = 0

$ErrorActionPreference = 'Stop'

Get-Content -LiteralPath $srcFile | ForEach-Object {
    $SampleCount++
    $ln++
    if ($ln -eq 1 -or $ln % 500 -eq 0)
    {
        $_
    }
} | Set-Content -LiteralPath $destFile

write-host $SampleCount

(get-content $destfile).count

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Thanks, Yes, I found that to be an effective workaround. See the Stack Overflow thread [here]https://stackoverflow.com/questions/78378535/powershell-out-file-append-silently-skips-a-few-rows-when-used-inside-foreach-l
The point of raising this ticket though was to alert that the Out-File cmdlet is not raising a terminating error when it cannot open the file for write access. The expected behaviour (as seen in PS5.1 with the native API call) is that it should as I illustrated above

Exception calling "AppendAllText" with "2" argument(s): "The process cannot access the file 
'\\UNCSHARE\Export_sample20240424_164810.txt' because it is being used 
by another process."

To be clear, I have found an alternative approach, but the behaviour of Out-File in PS Core, when writing to UNC network stream, does not make it apparent that any error has occurred.

I did try adding $ErrorActionPreference ="STOP" at the root of the script but it still didn't report an error.

Stack Overflow

Powershell out-file -append silently skips a few rows when used inside foreach loop

I am trying to extract a representative sample of a 200MB csv file by writing the header and every 500th row to a new file for testers to use. My first attempt was knowingly sub-optimal but seemed ...

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