Shell command doesn't give feedback until done

[Sarah Reichelt]

> The ampersand doesn't seem to work to run asynchronously.
>
Hi Bill,

Don't ask me to explain this one, but I mashed it together using some  
hints on various web sites and it does work asynchronously :-)

This is from a handler I use to ping a remote computer and it uses  
the ping command but doesn't wait for the result, instead reads it  
later from the file created by the command.

on startPingCheck pIP
   -- delete any existing result file
   put specialFolderPath("Desktop") & "/ping.txt" into tFileName
   if there is a file tFileName then delete file tFileName

   -- construct a command line and send it to the shell
   put "ping -c1 -n "  & pIP into tShellCmd
   put " > " & tFileName & " 2>&1 &" after tShellCmd
   get shell(tShellCmd)

   -- set up routine to keep checking for the result file
   -- read & parse the result when it appears
   send "checkForPingFile" to me in 1 second
end startPingCheck

If anyone can explain the "2>&1" section of the command, I would be  
most interested :-)
It seems to be critical but I have no idea why!

Sarah