Powershell pipe into exe and wait - powershell

Question

I am piping an array of data into a executable program but I need it to block after every call in the foreach loop. It will leave the loop before it even opens the program from the first call.
Set-Alias program "whatever.exe"
foreach ($data in $all_data)
{
$data| %{ program /command:update /path:"$_" /closeonend:2 }
}

Answer 1

I like PowerShell but I never really learned Invoke-Command. So whenever I need to run an EXE I always use cmd. If you type cmd /? you get its help, look at the "c" switch. I'd do something like this:
foreach ($data in $all_data){
$data |
Foreach-Object{
cmd /c "whatever.exe" /command:update /path:"$_" /closeonend:2
}
}
If you don't like the cmd /c thing you could use Jobs.
foreach ($data in $all_data){
$data |
Foreach-Object{
$job = Start-Job -InitializationScript {Set-Alias program "whatever.exe"} -ScriptBlock {program /command:update /path:"$($args[0])" /closeonend:2} -ArgumentList $_
while($job.Status -eq 'Running'){
Start-Sleep -Seconds 3
#Could make it more robust and add some error checking.
}
}
}

Answer 2

I can think of two ways to tackle this:
pipe your executable call to Out-Null
shell out the call to cmd.exe /c (as shown in #BobLobLaw's answer)
I made your sample code a little more specific so I could run and test my solutions; hopefully it'll translate. Here's what I started with to be equivalent to your sample code, i.e. the script executes with no waiting on the executable to finish.
# I picked a specific program
Set-Alias program "notepad.exe"
# And put some values in $all_data, specifically the paths to three text files.
$all_data = Get-Item B:\matt\Documents\*.txt
# This opens each file in notepad; three instances of notepad are running
# when the script finishes executing.
$all_data | %{ program "$_" }
Here's the same code as above, but piping to Out-Null forces the script to wait on each iteration of the loop.
# I picked a specific program
Set-Alias program "notepad.exe"
# And put some values in $all_data, specifically the paths to three text files.
$all_data = Get-Item B:\matt\Documents\*.txt
# Piping the executable call to out-null forces the script execution to wait
# for the program to complete. So in this example, the first document opens
# in notepad, but the second won't open until the first one is closed, and so on.
$all_data | %{ program "$_" | Out-Null}
And, lastly, the same code (more or less) using cmd /c to call the executable and make the script wait.
# Still using notepad, but I couldn't work out the correct call for
# cmd.exe using Set-Alias. We can do something similar by putting
# the program name in a plain old variable, though.
#Set-Alias program "notepad.exe"
$program = "notepad.exe"
# Put some values in $all_data, specifically the paths to three text files.
$all_data = Get-Item B:\matt\Documents\*.txt
# This forces script execution to wait until the call to $program
# completes. Again, the first document opens in notepad, but the second
# won't open until the first one is closed, and so on.
$all_data | %{ cmd /c $program "$_" }

Answer 3

Depending on your scenario, wait-job might be overkill. If you have a programmatic way to know that whatever.exe has done its thing, you could try something like
do {start-sleep -sec 2} until ($done -eq $true)
Oh and.