Wait for file copy?

AndrewM

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Aug 22, 2008, 10:02:01 AM8/22/08

to

$logs | Add-Zip( $smtp_archive_folder.FullName + "\" +
$date.ToString("yyyyMM") + ".zip")
$logs | Remove-Item

From Add-Zip
foreach($file in $input)
{
$zipPackage.CopyHere($file.FullName)
Start-sleep -milliseconds 500
}

Add-Zip uses XP/2003's compressed folders and the .copyhere method. My
problem is that second line executes while the Add-Zip is still churning
through the files in $logs, so files are deleted before they're archived.
Short of sleeping for an arbitrary amount of time (5,10,20 seconds), is there
any way I can wait on the copy? I tried replacing copyhere with movehere -
the files were still created in the zip file, but they were not removed from
the source location.

Alex K. Angelopoulos at

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Aug 22, 2008, 2:51:24 PM8/22/08

to

The real problem occurs in what you didn't show; whatever Add-Zip works
from, it's performing operations asynchronously. If $zipPackage represents a
custom component of some kind, it may also have a synchronous copy command,
which will wait until it finishes to return. If instead it's just a
reference to a Shell.Application namespace reference to a zip file, the
answer is not so good. The Shell.Application methods are basically all
asynchronous because they're designed for GUI use, where actual return to
the caller would be pointless; instead, it raises events to the desktop
shell. If this is the case, there are two likely solutions.

(1) Start out with a count of the files in the zip file - I think it should
be $zipPackage.Items().Count - and start a sleep loop that waits until it
increments by one. It should look like this:

$zippedCount = $zipPackage.Items().Count
while($zipPackage.Items().Count -lt ($zippedCount + 1) ){
Start-Sleep -milliseconds 20}

The one problem with this method is that if you can't copy a particular
file, or if you copy over a pre-existing file in the zip archive, you won't
get the count to increment by one.

(2) Use a library designed for this kind of problem. One possibility is this
one, which is free and open source:
http://www.icsharpcode.net/OpenSource/SharpZipLib/
I suspect you will be _much_ happier with the results of that, rather than
using Shell.Application for this particular problem.

"AndrewM" <And...@discussions.microsoft.com> wrote in message
news:5E8F764C-7E93-48E2...@microsoft.com...

AndrewM

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Aug 22, 2008, 3:03:03 PM8/22/08

to

Thanks - that makes perfect sense. I'll give the first option a try (I am
using a Shell.Application namespace reference to a zip). I'm archiving old,
daily smtp logs, so I shouldn't have the problem of copying over an
identically named file in the destination zip. If I run into problems, I'll
look into the library you linked.

Thanks again - I appreciate the detail in your reply.

Shay Levy [MVP]

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Aug 23, 2008, 3:15:13 PM8/23/08

to

Hi AndrewM,

Piping to out-null should wait for Add-Zip to complete before moving on to
the next command:

PS > $logs | Add-Zip... | out-null

You may also want to check Write-Zip from PowerShell Community Extensions
(PSCX) @ http://www.codeplex.com/PowerShellCX

---
Shay Levy
Windows PowerShell MVP
http://blogs.microsoft.co.il/blogs/ScriptFanatic

A> $logs | Add-Zip( $smtp_archive_folder.FullName + "\" +
A> $date.ToString("yyyyMM") + ".zip")
A> $logs | Remove-Item
A> From Add-Zip
A> foreach($file in $input)
A> {
A> $zipPackage.CopyHere($file.FullName)
A> Start-sleep -milliseconds 500
A> }
A> Add-Zip uses XP/2003's compressed folders and the .copyhere method.
A> My problem is that second line executes while the Add-Zip is still
A> churning through the files in $logs, so files are deleted before
A> they're archived. Short of sleeping for an arbitrary amount of time
A> (5,10,20 seconds), is there any way I can wait on the copy? I tried
A> replacing copyhere with movehere - the files were still created in
A> the zip file, but they were not removed from the source location.
A>

Alex K. Angelopoulos at

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Aug 23, 2008, 3:21:24 PM8/23/08

to

Yeah, that makes sense. You may want to poison the sleep loop, though, so if
nothing changes after a while it shouts at you and dies.

"AndrewM" <And...@discussions.microsoft.com> wrote in message

news:AE8B56B0-980F-473B...@microsoft.com...

leslacroix

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Dec 16, 2009, 10:07:22 PM12/16/09

to

Try this:

foreach($file in $input)
{
$zipPackage.CopyHere($file.FullName)
$maxLoops = 2*60*10 # 2 minutes
while ($zipPackage.items().item($_.name) -eq $null) {
if (--$maxLoops -le 0) {
Throw "timeout exceeded"
}
Start-sleep -milliseconds 100
}
}

The inner while loop waits up to 2 minutes for the item to appear in the zip folder's item list, and throws an error if it doesn't. Not exactly complete error checking, but it's better than nothing.