Trim Trailing Whitespace from All Files in a Directory

This one liner trims trailing whitespace from every file in the current directory.

dir -rec -file | % { $t = $_ | gc | % { $_.TrimEnd() }; sc $_.FullName $t; }  

Annotated Version: Note that in the outer loop $_ refers to the current file and in the inner loop $_ refers to the current line of text.

# loop thru each file
dir -Recurse -File | ForEach-Object  
{ 
    # for each file, loop thru each line of text and trim each one
    $trimmed = $_ | Get-Content | ForEach-Object 
    { 
        $_.TrimEnd() 
    };

    # write the trimmed text back to the file
    Set-Content $_.FullName $trimmed; 
}

Removing all trailing white-space in one fell swoop can be helpful when working with legacy code.