Problem running multiple folder actions at the same time

Question

Hi,
Does anyone have some experience running multiple folder actions at the same time?
I've written a Applescript folder action that processes some files. When adding some files, the script starts and all goes well. The processing of each file takes a few minutes, but all files are processed correctly.
However, when adding some new files to the dropfolder, while the folder action is all ready processing other files dropped a few minutes earlier, the process that is all ready running immediately aborts and the folder action is relaunched on the new files, leaving the old files for what they are...
The same problem occurs with multiple folders, each having a folder action attached. When dropping files in "Folder A", the script starts processing. But if someone droppes files in "Folder B", The script of folder A aborts, and the script of folder B starts processing. When adding more files to the folders, the result is the same. In some casses, when the last dropped files are processed, the os continues where the operation was aborted on the previous files. But this not always happens. To make things worse, when you remove the items from the folders afterwords, the folder actions starts running again on items no longer present in the folder !!!!
Does anyone know how I can prevent the folder action being aborted when new files are dropped and placing the new files in "Hold", until the previous files are processed? How can I prevent a folder action being aborted when a item is dropped into another folder?
I've written a small script to test this behaviour. Just create one or more folders and attach the script below. Drop a item into the folder, wait a few seconds and drop another one in the same or another folder. To monitor what happens please check the console.
on adding folder items to this_folder after receiving added_items
          set FolderName to this_folder as string
          set ItemName to added_items as string
          repeat with theIncrementValue from 1 to 15
  delay 2
                    do shell script ("logger \"Folder: " & FolderName & "  -  Item: " & ItemName & "  -  Step: " & theIncrementValue & "\"")
          end repeat
          do shell script ("logger \"Folder: " & FolderName & "  -  Item: " & ItemName & "  -  Done...\"")
end adding folder items to
Thanks for any feedback.

Answer 1

That is pretty much the way Folder Actions work, especially since AppleScript is not multi-threaded.  If you are using them as some intermediate step in a workflow, you might rethink the way you are handling the files (for example, use a droplet instead).  Other options would be using launchd to watch a path or a shell script on a different thread.