Run another command-line app from PowerShell

Question

I think this has been asked many times yet I can't find an answer that works for me.

I need to construct a command line from variables.
I need to run that command line executable.
I need to have the results spew out onto the same screen as my script.

I'm trying to run Putty SCP with a custom source and destination.

I've messed around with & and Invoke-Expression but its impossible. Some simple #1 use-case things in PowerShell are so incredibly hard they eat away at all that's good about it.

The only way I can see to do this is to run it within a new Process instance and setup all the output redirection and then pipe it back out on the PS screen after it finished.

And I know this could fail because the output buffer can get full unless you're hooked-into the events and are scooping it out.

The other way is to write my command line to a batch file and run that.

Any help appreciated. There has to be a simpler way.

Edit

For example:

[string]$scpPath = Find-PathToPuttyScpExecutable;
[string]$scpArguments = "-v -r -pw " + $MarkLogicServerPassword + " " + $MarkLogicSourcePath + " " + $MarkLogicServerUserName + "@" + $ServerName + ":" + $MarkLogicDestinationRootPath

I need to execute $scpPath + " " + $scpArguments.

Third way is to write a CmdLet in C# but although I've done this in the past, I want to avoid loading a module. — Luke Puplett
– Luke Puplett, Commented Mar 20, 2013 at 13:09
"I've messed around with & and Invoke-Expression but its impossible" - I'm pretty sure it's not. Post your code & point out what isn't working, and someone can try to help. Otherwise, this starts sounding like a rant. — alroc
– alroc, Commented Mar 20, 2013 at 13:14
post the exe name, its parameters you need and what variables you are plugging in and also mention where they go — Andy Arismendi
– Andy Arismendi, Commented Mar 20, 2013 at 13:17
Hmm/Grr. I tried to post a screen dump but the .png that Snipping Tool makes isn't understood by SO! — Luke Puplett
– Luke Puplett, Commented Mar 20, 2013 at 13:23
Screenshots of code are terrible anyway. Can't copy/paste, can't search. — alroc
– alroc, Commented Mar 20, 2013 at 14:05

Joey · Accepted Answer · 2013-03-20 13:32:27Z

4

Don't get so attached to strings. Just run commands with arguments:

[string]$scpPath = Find-PathToPuttyScpExecutable;
&$scpPath -v -r -pw $MarkLogicServerPassword $MarkLogicSourcePath "$($MarkLogicServerUserName)@$($ServerName):$($MarkLogicDestinationRootPath)"

PowerShell will handle the quoting for you. In most cases it works well and I doubt you'll stumble over the edge cases here.

If you have to create the argument list on the fly, then you should use an array and pass that:

$scpArguments = '-v',
                '-r',
                '-pw',
                $MarkLogicServerPassword,
                $MarkLogicSourcePath,
                "$($MarkLogicServerUserName)@$($ServerName):$($MarkLogicDestinationRootPath)"

&$scpPath @scpArguments

answered Mar 20, 2013 at 13:32

Joey

357k88 gold badges704 silver badges699 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Luke Puplett Over a year ago

I did not see that coming. Must adjust mental model. Thanks Joey.

Andy Arismendi Over a year ago

Powershell needs either an array of string args or spaces between them on the line so it can tokenize them. A single string with spaces in it will be interpreted as a single token.

Collectives™ on Stack Overflow

Run another command-line app from PowerShell

1 Answer 1

2 Comments

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Related