Progress during large file copy (Copy-Item & Write-Progress?)

Question

Is there any way to copy a really large file (from one server to another) in Powershell AND display it's progress?

There are solutions out there to use Write-Progress in conjunction with looping to copy many files and display progress. However I can't seem to find anything that would show progress of a single file.

Any thoughts?

Answer 1

Not that I'm aware of. I wouldn't recommend using copy-item for this anyway. I don't think it has been designed to be robust like robocopy.exe to support retry which you would want for extremely large file copies over the network.

Answer 2

I haven't heard about progress with Copy-Item. If you don't want to use any external tool, you can experiment with streams. The size of buffer varies, you may try different values (from 2kb to 64kb).

function Copy-File {
    param( [string]$from, [string]$to)
    $ffile = [io.file]::OpenRead($from)
    $tofile = [io.file]::OpenWrite($to)
    Write-Progress -Activity "Copying file" -status "$from -> $to" -PercentComplete 0
    try {
        [byte[]]$buff = new-object byte[] 4096
        [int]$total = [int]$count = 0
        do {
            $count = $ffile.Read($buff, 0, $buff.Length)
            $tofile.Write($buff, 0, $count)
            $total += $count
            if ($total % 1mb -eq 0) {
                Write-Progress -Activity "Copying file" -status "$from -> $to" `
                   -PercentComplete ([int]($total/$ffile.Length* 100))
            }
        } while ($count -gt 0)
    }
    finally {
        $ffile.Close()
        $tofile.Close()
    }
}