adding a timeout to batch/powershell - powershell

Question

$fullnamexp = ((net user $winxp /domain | Select-String "Full Name") -replace "Full Name","").Trim();
If $winxp cannot be found, the command will hang, is there a timeout I can use with this to make it move on after 5-10 seconds? Not sure where I would put it.
Edit- I use this to pull the username:
$reg = [Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey('LocalMachine', $tag1)
$key = $reg.OpenSubKey('SOFTWARE\Microsoft\Windows NT\CurrentVersion\WinLogon')
$winxp = $key.GetValue('DefaultUserName') -replace '^.*?\\'
$winxp is then a login name such as ajstepanik then I put it into: $fullnamexp = ((net user $winxp /domain | Select-String "Full Name") -replace "Full Name","").Trim();
1.21.2014 Update
$timeoutSeconds = 5
$code = {
((net user $winxp /domain | Select-String "Full Name") -replace "Full Name","").Trim(); # your commands here, e.g.
}
$j = Start-Job -ScriptBlock $code
if (Wait-Job $j -Timeout $timeoutSeconds) { $fullnamexp = Receive-Job $j }
Remove-Job -force $j

Answer 1

While #mjolinor may have indeed provided you an alternative approach, here is a direct answer to your general question: how do you force a timeout in PowerShell?
Wrap whatever you wish to time-limit in a script block, run that as a job, then use the Wait-Job cmdlet to time-limit the operation. Wait-Job will return either at the end of the timeout period or when the script block completes, whichever occurs first. After Wait-Job returns, you can examine the job state ($j.state) to determine whether it was interrupted or not, if it matters to you.
$timeoutSeconds = 5 # set your timeout value here
$j = Start-Job -ScriptBlock {
# your commands here, e.g.
Get-Process
}
"job id = " + $j.id # report the job id as a diagnostic only
Wait-Job $j -Timeout $timeoutSeconds | out-null
if ($j.State -eq "Completed") { "done!" }
elseif ($j.State -eq "Running") { "interrupted" }
else { "???" }
Remove-Job -force $j #cleanup
2014.01.18 Update
Here is a bit more streamlining approach that also includes the practical step of getting information out of the script block with Receive-Job, assuming what you want is generated on stdout:
$timeoutSeconds = 3
$code = {
# your commands here, e.g.
Get-ChildItem *.cs | select name
}
$j = Start-Job -ScriptBlock $code
if (Wait-Job $j -Timeout $timeoutSeconds) { Receive-Job $j }
Remove-Job -force $j

Answer 2

You can use Start-Sleep to pause the script:
Start-Sleep -s 5

Answer 3

net doesn't explicitly allow you to set a time out on it's operations, but you could check out this link on changing the ipv4 timeout for your sockets:
http://www.cyberciti.biz/tips/linux-increasing-or-decreasing-tcp-sockets-timeouts.html
The only thing else I could imagine is spawning a worker thread but I don't even know if that's possible in bash, I'm not fluid enough in it to answer that; plus it opens you up to sync problems and all sorts of multi threaded issues beyond what you're trying to accomplish quickly in a bash script to begin with! :P

Answer 4

Does this help?
$query = (dsquery user -samid $winxp)
if ($query) {$fullnamexp = ($query | dsget user -display)[1].trim()}
$fullnamexp

Answer 5

This solution doesn't work for me. remove-job -force $j takes over 5 seconds in this example.
$timeoutseconds = 1
$start = get-date
$j = start-job -scriptblock { Resolve-DnsName 1.1.1.1 }
if (wait-job $j -timeout $timeoutseconds) { $fullnamexp = receive-job $j }
remove-job -force $j
(get-date) - $start
Days : 0
Hours : 0
Minutes : 0
Seconds : 5
Milliseconds : 342
Ticks : 53426422
TotalDays : 6.18361365740741E-05
TotalHours : 0.00148406727777778
TotalMinutes : 0.0890440366666667
TotalSeconds : 5.3426422
TotalMilliseconds : 5342.6422
Here's a simple timeout example with notepad:
notepad
if (-not $(wait-process notepad 10; $?)) { stop-process -name notepad }

Answer 6

$watchdog = 10 #seconds
$start_time = Get-Date
$j = Start-Job -ScriptBlock{
#timeout command
if ($true) {
$i = 0
while($true) {
Write-Host "Count: $i"
Start-Sleep -Milliseconds 100
$i++
}
}
write-host "Hello"
}
while($true) {
if ($j.HasMoreData) {
Receive-Job $j
Start-Sleep -Milliseconds 200
}
$current = Get-Date
$time_span = $current - $start_time
if ($time_span.TotalSeconds -gt $watchdog) {
write-host "TIMEOUT!"
Stop-Job $j
break
}
if (-not $j.HasMoreData -and $j.State -ne 'Running') {
write-host "Finished"
break
}
}
Remove-Job $j