In my Powershell script I'm setting machine-level environment variables with:
[Environment]::SetEnvironmentVariable("MY_VARIABLE", "MY_VALUE", "Machine")
Inside this same script, I am calling another application that will look for the variable above. Is there a way for me to reload the current session with the variables I created above?
No but you can also set the environment variables for the current process i.e. $env:MY_VARIABLE = 'MY_VALUE'. Any application you start should inherit the environment variables set in this fashion.
Related
I have run into a couple cases where I am trying to use a command via command line, but the command is not recognized. I have narrowed it down to an issue with environment variables. In each case, the variable is present when I retrieve the variable with the underlying C# method, but not with the shorthand, $env:myVariable
For example, if I retrieve the variable like this, I will get a value.
[Environment]::GetEnvironmentVariable('ChocolateyInstall', 'Machine')
But, if I retrieve the variable like this, nothing is returned
$env:ChocolateyInstall
I then have to do something like this to to get my command to work.
$env:ChocolateyInstall = [Environment]::GetEnvironmentVariable('ChocolateyInstall', 'Machine')
I have not been able to find a good explanation as to why I have to do this. I've looked at this documentation, but nothing stands out to me. Ideally, I would like to install a CLI and then not have to deal with checking for and assigning environment variables for the command to work.
When opening a PowerShell session, all permanently stored environment variables1 will be loaded into the Environment drive (Env:) of this current session (source):
The Environment drive is a flat namespace containing the environment
variables specific to the current user's session.
The documentation you linked states:
When you change environment variables in PowerShell, the change
affects only the current session. This behavior resembles the behavior
of the Set command in the Windows Command Shell and the Setenv command
in UNIX-based environments. To change values in the Machine or User
scopes, you must use the methods of the System.Environment class.
So defining/changing an environment variable like this:
$env:ChocolateyInstall = [Environment]::GetEnvironmentVariable('ChocolateyInstall', 'Machine')
Will change it for the current session, thus being immediately effective, but will also only be valid for the current session.
The methods of [System.Environment] are more fine grained. There you can choose which environment variable scope to address. There are three scopes available:
Machine
User
Process
The Process scope is equivalent to the Environment drive and covers the environment variables available in your current session. The Machine and the User scope address the permanently stored environment variables1. You can get variables from a particular scope like this:
[Environment]::GetEnvironmentVariable('ChocolateyInstall', 'Machine')
And set them with:
[Environment]::SetEnvironmentVariable('ChocolateyInstall', 'any/path/to/somewhere', 'Machine')
If you want to have new variables from the Machine or User scope available in your current PowerShell session, you have to create a new one. But don't open a new PowerShell session from your current PowerShell session, as it will then inherit all environment variables from your current PowerShell session (source):
Environment variables, unlike other types of variables in PowerShell,
are inherited by child processes, such as local background jobs and
the sessions in which module members run. This makes environment
variables well suited to storing values that are needed in both parent
and child processes.
So, to address the problem you described, you most probably changed your permanently stored environment variables1, while already having an open PowerShell session. If so, you just need to open a new (really new, see above) session and you will be able to access your environment variables via the Environment drive. Just to be clear, opening a new session will even reload environment variables of the Machine scope. There is no reboot required.
1 That are the environment variables you see in the GUI when going to the System Control Panel, selecting Advanced System Settings and on the Advanced tab, clicking on Environment Variable. Those variables cover the User and the Machine scope.
Alternatively, you can open this GUI directly by executing:
rundll32 sysdm.cpl,EditEnvironmentVariables
I am trying to add new Environment variable in my windows 10 system , i am using below powershell command to add System variable
$env:ITH_PYTHON_PATH = 'C:\Python27\Python.exe'
i can see command is successful in adding the new values, and i can get back value when i use command $env:ITH_PYTHON_PATH.
I cannot see updated path when i manually go to the system property Environment variable
After reboot $env:ITH_PYTHON_PATH is also not seen.
Is there any better way to add environment variable permanently?
Would something like this work?
[Environment]::SetEnvironmentVariable("ITH_PYTHON_PATH", "C:\Python27\Python.exe", "Machine")
I'm interested in using a script task to override one of these Bamboo plan variables for subsequent tasks but I'm not sure if it's possible or how to go about doing so. It appears that Bamboo allows for various levels of variable overrides for Build Plans all the way down to particular branches however they all seem to require defining the values within the Bamboo UI. The problem with this is that it requires admin privileges to modify these variables whereas some of them need to be modified by developers that do not have this level of access. As a solution I want to be able to specify some variable overrides in files that exist in the source repository itself.
Attempt 1: Overriding environment variables
I've attempted to set the environment variables exposed by Bamboo using a Powershell script and specifying something like $env:bamboo_xyz = 'ABC' but it doesn't seem to have an effect past the task context in which it was specified in. Presumably Bamboo must be re-setting the environment variables individually for each task or executing them within their own contexts but it's not clear to me exactly from the documentation.
UPDATE: It appears from some testing that environment variables set in one Script task are not available in subsequent Script tasks in the same Job. This leaves me with no apparent way to override variables based on anything other than hard coded values in Bamboo.
Attempt 2: Using the Bamboo Inject Variables Plugin task
I've tried using the Bamboo Inject Variables Plugin task to override variables but because what appears to be a required namespace parameter it only seems to be able to define new variables and not override existing ones.
Enviroment variables are only valid in the current session. So if bamboo starts one script ( one powershell session ) completes that and then start a new powershell script ( New Session ) the enviroment variable will not be kept.
So then there are a few options, set the variable in each script.
Or set it using registry at the start of the process. And if ncessary set it back to default value in the last step/script.
I've been looking everywhere to see which is the environment variable for the MSBuildExtensionsPath that I have in my TFS project file. How do I access this environment variable in PowerShell?
EDIT:
Out of the ones listed here, I am not sure which one I use.
The way you access env vars in PowerShell is:
$env:TF_BUILD_BINARIESDIRECTORY
That said, I don't see via your link an env var that corresponds to the MSBuild built-in variable MSBuildExtensionsPath. Why don't you pass that variable value into your PowerShell script as a parameter?
I am trying to set the environment variables of a user XYZ from the powershell of admin user ABC. I am using Start-Process to launch the powershell of user XYZ but i am not able to capture the output. All this process needs to be done in Java.
Can someone help me out.
Thanks
Ajax
When you change environment variables, the change affects only the current PowerShell session (like if you were using SET command in a Windows cmd). To make the changes permanent, you have to change them with a utility like SETX. You must also have permission to change the values.
Check this TechNet article on it: https://technet.microsoft.com/en-us/library/ff730964.aspx
Basically, you're going to want to set it using the .NET method at the machine scope:
[Environment]::SetEnvironmentVariable("TestVariable","Test Value","Machine")
You'll need to restart your Powershell session to be able to access the new environment variable after creating it.