Unix tail equivalent command in Windows Powershell

Question

I have to look at the last few lines of a large file (typical size is 500MB-2GB). I am looking for a equivalent of Unix command tail for Windows Powershell. A f

Answer 1

Using Powershell V2 and below, get-content reads the entire file, so it was of no use to me. The following code works for what I needed, though there are likely some issues with character encodings. This is effectively tail -f, but it could be easily modified to get the last x bytes, or last x lines if you want to search backwards for line breaks.

$filename = "\wherever\your\file\is.txt"
$reader = new-object System.IO.StreamReader(New-Object IO.FileStream($filename, [System.IO.FileMode]::Open, [System.IO.FileAccess]::Read, [IO.FileShare]::ReadWrite))
#start at the end of the file
$lastMaxOffset = $reader.BaseStream.Length

while ($true)
{
    Start-Sleep -m 100

    #if the file size has not changed, idle
    if ($reader.BaseStream.Length -eq $lastMaxOffset) {
        continue;
    }

    #seek to the last max offset
    $reader.BaseStream.Seek($lastMaxOffset, [System.IO.SeekOrigin]::Begin) | out-null

    #read out of the file until the EOF
    $line = ""
    while (($line = $reader.ReadLine()) -ne $null) {
        write-output $line
    }

    #update the last max offset
    $lastMaxOffset = $reader.BaseStream.Position
}

I found most of the code to do this here.