I have a service running that can invoke an external process to modify a text stream before it is returned to the service. The text stream is handed from the service to the external process on stdout and the modified result is read from the service on stdin. The external process (command) can in other words be used as a text "filter". I would like to use a powershell script to modify the text stream. I can successfully launch a script from the service on win 2008r2 using the command "powershell -executionpolicy bypass -noninteractive ./myscript.ps1".
I can make the script return text to the service on stdout using the write-host cmdlet. My problem is that I can't find a way to read the text on stdin in the script. Read-host doesn't seem to work as it requires an interactive shell.
I would like to avoid writing the stdout from the service to a tmp file and read that file in the script as the service is multithreaded (can launch more than one external command at a time) and tmp file management (locking, unique filenames etc) is not desired.
Is this possible or should I use for example Perl for this? Powershell seems compelling as it is preinstalled on all my win 2008 machines.
Just a guess - I would have a look at [Console]::In | gm -static.
Related
I'm using pwsh on linux to run some specific powershell modules.
I want to output the data received to file descriptor 3. I want data on file descriptor 3 as Powershell doesn't respect the convention that stdout is data and stderr is logging. I want file descriptor 3 to serve as our "data" file descriptor.
End goal is to be able to do something like this as we wrap this powershell call in Python and we'll redirect the file descriptor 3 data ourselves
pwsh -f script.ps1 3>data
PowerShell has no built-in way to output to streams other than stdout (1) and stderr (2) (more on that below.
Conceivably, you can roll your own output behavior with .NET API and/or P/Invoke calls, but that would be cumbersome.
However, this may not be required:
While it is true that - unfortunately - PowerShell by default sends output from all its output streams to stdout - see GitHub issue #7989 - you can redirect PowerShell error-stream to stderr, if you apply a 2> redirection on the caller's side.
The following call, e.g. from bash, demonstrates this:
# Prints just 'hi', because the error-stream output was
# redirected to stderr thanks to 2>, and due to targeting /dev/null, suppressed.
pwsh -noprofile -c '"hi"; Write-Error no!' 2>/dev/null
The downside is that if you want to print the stderr output too, you must capture it in a file and print it afterwards, which means that it (a) won't appear at the time it is being produced and (b) therefore won't be properly interleaved with any stdout output.
As an aside:
The current behavior of the PowerShell CLI (as of v7.2.x) is unfortunate not only with respect to how output streams are mapped, but also because it loads profile files by default.
There was talk about providing a separate CLI to address the latter problem, in the context of which the stream-mapping behavior could be fixed too, but nothing has happened so far: see GitHub issue #8072.
We have an application server running as a service, when some configuration is loaded it starts a bat script which has to run the powershell command Stop-ClusterGroup DRMSERVICES and then start it again.
The bat file works flawless when I manually execute it by dobbelt clicking. But when the service is running the bat, it does not finish, or execute the powershell command.
Bat file looks as follows
#echo off
powershell -command Stop-ClusterGroup DRMSERVICES
powershell -command Start-ClusterGroup DRMSERVICES
The service runs the bat file in silent mode, as a main difference.
I have tried with various switches including the -ExecutionPolicy Unrestricted and START /wait etc
Creating a seperate ps1 file and have the bat execute this instead.
All with the same output:
Manually executing the bat works
When the service executes the bat, it does not work.
I know the bat file is executed by the service, as inserting NET STOP servicename is working correct.
In the powershell event viewer I can also see event of the powershell commands take place.
The difference between manually executing and have the service execute the command in the event viewer, is event id 800 which states info about 'execution pipe' this is not present when the service is executing the bat.
The service does not wait for the powershell, and thus it does not have time to stop the cluster before exiting.
I'm lost whether this is a permission issue, syntax error or whatever.
Hopefully somebody can help
UPDATE:
I have tried with all proposed solutions, all with same result, the bat file works when double clicked, but the service does not execute the powershell command. Pure cmd is executed, as I can pipe to a txt file. I even got to a point when trying runas that the output log text wrote "insert administrator password"
I even managed to have our software guy change our software to call a powershell directly instead of a bat, same result. Powershell won't execute the command, this tells me it probably is permission, but everything have been set to log in as admin and run as admin for the sake of success, but still nothing.
I solved the problem.
Because the service is a 32bit process, it will execute a 32bit powershell.
FailoverClusters module only exists as a 64bit module.
By using %SystemRoot%\sysnative\WindowsPowershell\v1.0\powershell.exe
The service is able to open a 64bit session, and thus use the failover cluster module.
As a side note, the sysnative folder is only visible from a 32bit session, therefore it cannot be found via browsing in a 64bit os.
I think i have dealt with this kind of issue before, after the,
powershell -command Stop-ClusterGroup DRMSERVICES
you need to have cmd wait for a certain number of seconds, and then test if the DRMSERVICES is now stopped, if it is stopped then to start the DRMSERVICES again. This way cmd will keep waiting, and then check if the service has stopped.
After a certain number of tries, maybe have a way to stop checking and exit the script, for example it is trying to stop the service, and has run into a problem.
There is a timeout command in cmd
the following command starts the C++ application in new command window with process affinity set to 0xF.
start /affinity F test.ext arg1 arg2
But the above command opens a new cmd window and closes immediately when test.exe ends. I tried the following to get output but it doesn't do anything.
start /affinity F test.ext arg1 arg2 ^> out.txt
I appreciate if you know how to do this on powershell.
Thanks
About Redirection
The PowerShell redirection operators are as follows, where n
represents the stream number. The Success stream ( 1 ) is the default
if no stream is specified.
Operator Description
Syntax
> Send specified stream to a file. n>
>> Append specified stream to a file. n>>
>&1 Redirects the specified stream to the Success stream. n>&1
# Examples
# Example 1: Redirect errors and output to a file
dir 'C:\', 'fakepath' 2>&1 > .\dir.log
This example runs dir on one item that will succeed, and one that will
error.
It uses 2>&1 to redirect the Error stream to the Success stream, and >
to send the resultant Success stream to a file called dir.log
# Example 2: Send all Success stream data to a file
.\script.ps1 > script.log
This command sends all Success stream data to a file called script.log
Also, a possible duplicate of the following
How to pipe all output of .exe execution in Powershell?
How to redirect the output of a PowerShell to a file during its execution
See also
Running external commands, can or will require special
consideration.
PowerShell: Running Executables
Solve Problems with External Command Lines in PowerShell
Top 5 tips for running external commands in Powershell
Using Windows PowerShell to run old command line tools (and their
weirdest parameters)
Execution of external commands in PowerShell done right
Part 1
Part 2
Part 3
Quoting specifics
I want to execute .ps1 file in jmeter. I have pass the parameter as in image,but in output facing errors.The filename, directory name, or volume label syntax is incorrect.
Though the filename, directory name are correct.
Here is your problem:
Remove that quotation mark and everything should start working as expected
In general, you are making things overcomplicated.
Why do you need these cmd /c? Why just don't call powershell directly?
Normally powershell is in Windows PATH, there is no need to provide full path to it
So configure your OS Process Sampler as:
Command: powershell
Parameter: D:\Software\apache=jmeter-3.0\apache-jmeter-3.0\bin\TIP.ps1
See How to Run External Commands and Programs Locally and Remotely from JMeter article for more information on invoking 3rd-party processes from your JMeter test.
I know this is an old thread but since the response was not correct for me I found the solution to be this:
Using the OS Process Sampler you need to add as command powershell.exe and as variables exactly the following:
-executionpolicy
bypass
-file
fullpathToYourScript.ps1
This worked perfectly fine for me.
Context: Oracle Enterprise Manager has a feature to "execute host command." If into that feature I enter "dir c:\temp" then the output window echos the command and then shows a directory listing. If into that feature I enter "powershell dir c:\temp" the output window shows only the echo'd command. No directory listing. If on the target machine I enter those two commands in both cases I get the echo'd command followed by a directory listing.
I hypothesize that what I see in the cmd.exe window on the client blends two stdout streams: one from the cmd.exe itself and one from the invoked process (powershell dir c:\temp). The Oracle thing seems to recognize only the cmd.exe's stdout.
Is there some way I can force the stdout from the invoked process to be in the cmd.exe's stdout stream so that Oracle will recognize it and the thing I am trying to build will work?
I don't think you can directly pipe the output from one program back into STDOUT of a parent cmd.exe - assuming that is what Oracle is doing at some level.
That being said, you could try something clever like the following:
cmd /c "powershell -Command ""& echo Hello" > %TEMP%\a.txt & TYPE %TEMP\a.txt
Basically this is capturing the output from PowerShell, placing it in a temporary file, then dumping that file back onto STDOUT in cmd.exe. A nice touch would be cleaning up the temp file with a & DEL %TEMP%\a.txt on the end of the command.
You will probably need to toy around with the command line to account for any quirks in how Oracle is passing things along - my guess is that it is invoking cmd.exe /c directly so you can probably leave that part off.