If a process does not complete withing X amount of seconds, I want to execute some code (including killing that process). How can I do this?
Below is my current attempt. The problem here is that the code in the catch clause is never executed, even when the process times out.
$process = Start-Process cmd -ArgumentList "/k process.bat && exit" -PassThru
try {
Wait-Process $process.Id -Timeout 3
}
catch {
"Stopping process"
Stop-Process $process
}
Related
I want to repeatedly execute a program in a loop.
Sometimes, the program crashes, so I want to kill it so the next iteration can correctly start. I determine this via timeout.
I have the timeout working but cannot get the Exit Code of the program, which I also need to determine its result.
Before, I did not wait with timeout, but just used -wait in Start-Process, but this made the script hang if the started program crashed. With this setup I could correctly get the exit code though.
I am executing from ISE.
for ($i=0; $i -le $max_iterations; $i++)
{
$proc = Start-Process -filePath $programtorun -ArgumentList $argumentlist -workingdirectory $programtorunpath -PassThru
# wait up to x seconds for normal termination
Wait-Process -Timeout 300 -Name $programname
# if not exited, kill process
if(!$proc.hasExited) {
echo "kill the process"
#$proc.Kill() <- not working if proc is crashed
Start-Process -filePath "taskkill.exe" -Wait -ArgumentList '/F', '/IM', $fullprogramname
}
# this is where I want to use exit code but it comes in empty
if ($proc.ExitCode -ne 0) {
# update internal error counters based on result
}
}
How can I
Start a process
Wait for it to orderly execute and finish
Kill it if it is crashed (e. g. hits timeout)
get exit code of process
You can terminate the process more simply using $proc | kill or $proc.Kill(). Be aware, that you won't be able to retrieve a exit code in this case, you should rather just update the internal error counter:
for ($i=0; $i -le $max_iterations; $i++)
{
$proc = Start-Process -filePath $programtorun -ArgumentList $argumentlist -workingdirectory $programtorunpath -PassThru
# keep track of timeout event
$timeouted = $null # reset any previously set timeout
# wait up to x seconds for normal termination
$proc | Wait-Process -Timeout 4 -ErrorAction SilentlyContinue -ErrorVariable timeouted
if ($timeouted)
{
# terminate the process
$proc | kill
# update internal error counter
}
elseif ($proc.ExitCode -ne 0)
{
# update internal error counter
}
}
Let's say you have the following script saved in a file outermost.ps1:
powershell.exe -Command "while ( 1 -eq 1 ) {} "
echo "Done"
When running outermost.ps1 you can only abort this by pressing Ctrl+C, and no output will be written to console. How can I modify it so that the outermost script continues and executes echo "Done" when Ctrl+C is pressed?
This is a simplified version of a real-life scenario where the inner script is actually an executable which only is stoppable by pressing Ctrl+C.
Edit: The script could also be:
everlooping.exe
echo "Done"
but I wanted to provide an example everyone could copy-paste into an editor if they wanted to "try at home".
Start your infinite command/statement as a job, make your PowerShell script process Ctrl+C as regular input (see here), and stop the job when that input is received:
[Console]::TreatControlCAsInput = $true
$job = Start-Job -ScriptBlock {
powershell.exe -Command "while ( 1 -eq 1 ) {} "
}
while ($true) {
if ([Console]::KeyAvailable) {
$key = [Console]::ReadKey($true)
if (($key.Modifiers -band [ConsoleModifiers]::Control) -and $key.Key -eq 'c') {
$job.StopJob()
break
}
}
Start-Sleep -Milliseconds 100
}
Receive-Job -Id $job.Id
Remove-Job -Id $job.Id
echo "Done"
If you need to retrieve output from the job while it's running, you can do so like this in an else branch to the outer if statement:
if ($job.HasMoreData) { Receive-Job -Id $job.Id }
The simplest solution to this is:
Start-Process -Wait "powershell.exe" -ArgumentList "while ( 1 -eq 1 ) {}"
echo "Done"
This will spawn a second window unlinke ansgar-wiechers solution, but solves my problem with the least amount of code.
Thanks to Jaqueline Vanek for the tip
I'm trying to run a program from PowerShell, wait for the exit, then get access to the ExitCode, but I am not having much luck. I don't want to use -Wait with Start-Process, as I need some processing to carry on in the background.
Here's a simplified test script:
cd "C:\Windows"
# ExitCode is available when using -Wait...
Write-Host "Starting Notepad with -Wait - return code will be available"
$process = (Start-Process -FilePath "notepad.exe" -PassThru -Wait)
Write-Host "Process finished with return code: " $process.ExitCode
# ExitCode is not available when waiting separately
Write-Host "Starting Notepad without -Wait - return code will NOT be available"
$process = (Start-Process -FilePath "notepad.exe" -PassThru)
$process.WaitForExit()
Write-Host "Process exit code should be here: " $process.ExitCode
Running this script will cause Notepad to be started. After this is closed manually, the exit code will be printed, and it will start again, without using -wait. No ExitCode is provided when this is quit:
Starting Notepad with -Wait - return code will be available
Process finished with return code: 0
Starting Notepad without -Wait - return code will NOT be available
Process exit code should be here:
I need to be able to perform additional processing between starting the program and waiting for it to quit, so I can't make use of -Wait. How can I do this and still have access to the .ExitCode property from this process?
There are two things to remember here. One is to add the -PassThru argument and two is to add the -Wait argument. You need to add the wait argument because of this defect.
-PassThru [<SwitchParameter>]
Returns a process object for each process that the cmdlet started. By default,
this cmdlet does not generate any output.
Once you do this a process object is passed back and you can look at the ExitCode property of that object. Here is an example:
$process = start-process ping.exe -windowstyle Hidden -ArgumentList "-n 1 -w 127.0.0.1" -PassThru -Wait
$process.ExitCode
# This will print 1
If you run it without -PassThru or -Wait, it will print out nothing.
The same answer is here: How do I run a Windows installer and get a succeed/fail value in PowerShell?
It's also worth noting that there's a workaround mentioned in the "defect report" link above, which is as following:
# Start the process with the -PassThru command to be able to access it later
$process = Start-Process 'ping.exe' -WindowStyle Hidden -ArgumentList '-n 1 -w 127.0.0.1' -PassThru
# This will print out False/True depending on if the process has ended yet or not
# Needs to be called for the command below to work correctly
$process.HasExited
# This will print out the actual exit code of the process
$process.GetType().GetField('exitCode', 'NonPublic, Instance').GetValue($process)
While trying out the final suggestion above, I discovered an even simpler solution. All I had to do was cache the process handle. As soon as I did that, $process.ExitCode worked correctly. If I didn't cache the process handle, $process.ExitCode was null.
example:
$proc = Start-Process $msbuild -PassThru
$handle = $proc.Handle # cache proc.Handle
$proc.WaitForExit();
if ($proc.ExitCode -ne 0) {
Write-Warning "$_ exited with status code $($proc.ExitCode)"
}
Two things you could do I think...
Create the System.Diagnostics.Process object manually and bypass Start-Process
Run the executable in a background job (only for non-interactive processes!)
Here's how you could do either:
$pinfo = New-Object System.Diagnostics.ProcessStartInfo
$pinfo.FileName = "notepad.exe"
$pinfo.RedirectStandardError = $true
$pinfo.RedirectStandardOutput = $true
$pinfo.UseShellExecute = $false
$pinfo.Arguments = ""
$p = New-Object System.Diagnostics.Process
$p.StartInfo = $pinfo
$p.Start() | Out-Null
#Do Other Stuff Here....
$p.WaitForExit()
$p.ExitCode
OR
Start-Job -Name DoSomething -ScriptBlock {
& ping.exe somehost
Write-Output $LASTEXITCODE
}
#Do other stuff here
Get-Job -Name DoSomething | Wait-Job | Receive-Job
The '-Wait' option seemed to block for me even though my process had finished.
I tried Adrian's solution and it works. But I used Wait-Process instead of relying on a side effect of retrieving the process handle.
So:
$proc = Start-Process $msbuild -PassThru
Wait-Process -InputObject $proc
if ($proc.ExitCode -ne 0) {
Write-Warning "$_ exited with status code $($proc.ExitCode)"
}
Or try adding this...
$code = #"
[DllImport("kernel32.dll")]
public static extern int GetExitCodeProcess(IntPtr hProcess, out Int32 exitcode);
"#
$type = Add-Type -MemberDefinition $code -Name "Win32" -Namespace Win32 -PassThru
[Int32]$exitCode = 0
$type::GetExitCodeProcess($process.Handle, [ref]$exitCode)
By using this code, you can still let PowerShell take care of managing redirected output/error streams, which you cannot do using System.Diagnostics.Process.Start() directly.
Here's a variation on this theme. I want to uninstall Cisco Amp, wait, and get the exit code. But the uninstall program starts a second program called "un_a" and exits. With this code, I can wait for un_a to finish and get the exit code of it, which is 3010 for "needs reboot". This is actually inside a .bat file.
If you've ever wanted to uninstall folding#home, it works in a similar way.
rem uninstall cisco amp, probably needs a reboot after
rem runs Un_A.exe and exits
rem start /wait isn't useful
"c:\program files\Cisco\AMP\6.2.19\uninstall.exe" /S
powershell while (! ($proc = get-process Un_A -ea 0)) { sleep 1 }; $handle = $proc.handle; 'waiting'; wait-process Un_A; exit $proc.exitcode
I'm running this simple script of MSIEXEC uninstall:
$script = {
invoke-expression "msiexec /qn /x '{C5CF41A6-A65A-4BB3-8C6C-87FF4A730EFD}' "
$logcheck = ""
while($true)
{
if($logcheck -match "Removal success or error status: 0")
{
return
}
else
{
start-sleep -Seconds 1
[string]$logcheck = get-eventlog -logname application -newest 1 | foreach-object {$_.message}
}
}
}
Invoke-Command -computername Comp-name -Credential Domain\user -scriptblock $script
Write-Host "Done"
Everything seems to work great, the MSI was being uninstalled successfully but the powershell process stays open and doesn't stop.
Any idea how can I stop it?
It doesn't stop because of the while($true)
That logcheck is not really full proof, it gets the newest log item and then checks for status "Removal success or error status: 0". If any other application adds an entry to the log at the same time, this loop will run forever.
Better to get all log items since a certain date, e.g. start datetime of msiexec and look for the success message. (and not use the loop)
I'm trying to run a program from PowerShell, wait for the exit, then get access to the ExitCode, but I am not having much luck. I don't want to use -Wait with Start-Process, as I need some processing to carry on in the background.
Here's a simplified test script:
cd "C:\Windows"
# ExitCode is available when using -Wait...
Write-Host "Starting Notepad with -Wait - return code will be available"
$process = (Start-Process -FilePath "notepad.exe" -PassThru -Wait)
Write-Host "Process finished with return code: " $process.ExitCode
# ExitCode is not available when waiting separately
Write-Host "Starting Notepad without -Wait - return code will NOT be available"
$process = (Start-Process -FilePath "notepad.exe" -PassThru)
$process.WaitForExit()
Write-Host "Process exit code should be here: " $process.ExitCode
Running this script will cause Notepad to be started. After this is closed manually, the exit code will be printed, and it will start again, without using -wait. No ExitCode is provided when this is quit:
Starting Notepad with -Wait - return code will be available
Process finished with return code: 0
Starting Notepad without -Wait - return code will NOT be available
Process exit code should be here:
I need to be able to perform additional processing between starting the program and waiting for it to quit, so I can't make use of -Wait. How can I do this and still have access to the .ExitCode property from this process?
There are two things to remember here. One is to add the -PassThru argument and two is to add the -Wait argument. You need to add the wait argument because of this defect.
-PassThru [<SwitchParameter>]
Returns a process object for each process that the cmdlet started. By default,
this cmdlet does not generate any output.
Once you do this a process object is passed back and you can look at the ExitCode property of that object. Here is an example:
$process = start-process ping.exe -windowstyle Hidden -ArgumentList "-n 1 -w 127.0.0.1" -PassThru -Wait
$process.ExitCode
# This will print 1
If you run it without -PassThru or -Wait, it will print out nothing.
The same answer is here: How do I run a Windows installer and get a succeed/fail value in PowerShell?
It's also worth noting that there's a workaround mentioned in the "defect report" link above, which is as following:
# Start the process with the -PassThru command to be able to access it later
$process = Start-Process 'ping.exe' -WindowStyle Hidden -ArgumentList '-n 1 -w 127.0.0.1' -PassThru
# This will print out False/True depending on if the process has ended yet or not
# Needs to be called for the command below to work correctly
$process.HasExited
# This will print out the actual exit code of the process
$process.GetType().GetField('exitCode', 'NonPublic, Instance').GetValue($process)
While trying out the final suggestion above, I discovered an even simpler solution. All I had to do was cache the process handle. As soon as I did that, $process.ExitCode worked correctly. If I didn't cache the process handle, $process.ExitCode was null.
example:
$proc = Start-Process $msbuild -PassThru
$handle = $proc.Handle # cache proc.Handle
$proc.WaitForExit();
if ($proc.ExitCode -ne 0) {
Write-Warning "$_ exited with status code $($proc.ExitCode)"
}
Two things you could do I think...
Create the System.Diagnostics.Process object manually and bypass Start-Process
Run the executable in a background job (only for non-interactive processes!)
Here's how you could do either:
$pinfo = New-Object System.Diagnostics.ProcessStartInfo
$pinfo.FileName = "notepad.exe"
$pinfo.RedirectStandardError = $true
$pinfo.RedirectStandardOutput = $true
$pinfo.UseShellExecute = $false
$pinfo.Arguments = ""
$p = New-Object System.Diagnostics.Process
$p.StartInfo = $pinfo
$p.Start() | Out-Null
#Do Other Stuff Here....
$p.WaitForExit()
$p.ExitCode
OR
Start-Job -Name DoSomething -ScriptBlock {
& ping.exe somehost
Write-Output $LASTEXITCODE
}
#Do other stuff here
Get-Job -Name DoSomething | Wait-Job | Receive-Job
The '-Wait' option seemed to block for me even though my process had finished.
I tried Adrian's solution and it works. But I used Wait-Process instead of relying on a side effect of retrieving the process handle.
So:
$proc = Start-Process $msbuild -PassThru
Wait-Process -InputObject $proc
if ($proc.ExitCode -ne 0) {
Write-Warning "$_ exited with status code $($proc.ExitCode)"
}
Or try adding this...
$code = #"
[DllImport("kernel32.dll")]
public static extern int GetExitCodeProcess(IntPtr hProcess, out Int32 exitcode);
"#
$type = Add-Type -MemberDefinition $code -Name "Win32" -Namespace Win32 -PassThru
[Int32]$exitCode = 0
$type::GetExitCodeProcess($process.Handle, [ref]$exitCode)
By using this code, you can still let PowerShell take care of managing redirected output/error streams, which you cannot do using System.Diagnostics.Process.Start() directly.
Here's a variation on this theme. I want to uninstall Cisco Amp, wait, and get the exit code. But the uninstall program starts a second program called "un_a" and exits. With this code, I can wait for un_a to finish and get the exit code of it, which is 3010 for "needs reboot". This is actually inside a .bat file.
If you've ever wanted to uninstall folding#home, it works in a similar way.
rem uninstall cisco amp, probably needs a reboot after
rem runs Un_A.exe and exits
rem start /wait isn't useful
"c:\program files\Cisco\AMP\6.2.19\uninstall.exe" /S
powershell while (! ($proc = get-process Un_A -ea 0)) { sleep 1 }; $handle = $proc.handle; 'waiting'; wait-process Un_A; exit $proc.exitcode