how to use powershell to copy file and retain original timestamp

Question

I would like to copy some files or a folder of files from one file server to another. However, I want to keep the original timestamp and file attributes so that the newly copied files will have the same timestamp of the original files. Thanks in advance on any answer.

Solution 1

Here's a powershell function that'll do what you're asking... It does absolutely no sanity checking, so caveat emptor...

function Copy-FileWithTimestamp {
[cmdletbinding()]
param(
    [Parameter(Mandatory=$true,Position=0)][string]$Path,
    [Parameter(Mandatory=$true,Position=1)][string]$Destination
)

    $origLastWriteTime = ( Get-ChildItem $Path ).LastWriteTime
    Copy-Item -Path $Path -Destination $Destination
    (Get-ChildItem $Destination).LastWriteTime = $origLastWriteTime
}

Once you've run loaded that, you can do something like:

Copy-FileWithTimestamp foo bar

(you can also name it something shorter, but with tab completion, not that big of a deal...)

Solution 2

Here is how you can copy over the time stamps, attributes, and permissions.

$srcpath = 'C:\somepath'
$dstpath = 'C:\anotherpath'
$files = gci $srcpath

foreach ($srcfile in $files) {
  # Build destination file path
  $dstfile = [io.FileInfo]($dstpath, '\', $srcfile.name -join '')

  # Copy the file
  cp $srcfile.FullName $dstfile.FullName

  # Make sure file was copied and exists before copying over properties/attributes
  if ($dstfile.Exists) {
    $dstfile.CreationTime = $srcfile.CreationTime
    $dstfile.LastAccessTime = $srcfile.LastAccessTime
    $dstfile.LastWriteTime = $srcfile.LastWriteTime
    $dstfile.Attributes = $srcfile.Attributes
    $dstfile.SetAccessControl($srcfile.GetAccessControl())
  }
}

Solution 3

If you are okay with a two-step solution; then

• First copy files over from source to dest
• loop over each file; and each attribute for each file
• copy attributes from source to destination

Try this technique to copy file attributes from one file to another. (I have illustrated this with LastWriteTime; I am sure you can extend it for other attributes).

#Created two dummy files
PS> echo hi > foo
PS> echo there > bar

# Get attributes for first file
PS> $timestamp = gci "foo"
PS> $timestamp.LastWriteTime

06 February 2014 09:25:47

# Get attributes for second file
PS> $t2 = gci "bar"
PS> $t2.LastWriteTime

06 February 2014 09:25:53

# Simply overwrite
PS> $t2.LastWriteTime = $timestamp.LastWriteTime

# Ta-Da!
PS> $t2.LastWriteTime

06 February 2014 09:25:47

Comments

[Guy Thomas]

Neat. It worked when I tested Copy-FileWithTimestamp.

[Hunter Eidson]

I haven't tested it, but I would expect it to fail spectacularly if you tried to use a wildcard in the copy the way I wrote that function...

[Guy Thomas]

I merely wanted to help the community by reporting that I tried your code and it worked. I did not mean to imply that I was giving an endorsement for use in a production network.

[Hunter Eidson]

No problem... my comment was more of an afterthought when I was driving into the office today... :)

[jpaugh]

Using Get-Item would probably be safer, especially if $Destination is a directory.

[stackprotector]

Nice reminder to take into account all three timestamps and not just LastWriteTime.