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")
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
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.
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.
I'm having this weird situation :
My user's and system's PATH variable is different than the PATH in powershell.
When I do :
PS C:\$env:path
C:\Windows\System32\WindowsPowerShell\v1.0\;c:\oldpath
However this is not correct, it looks like it stuck on some old PATH variable of my system, so none of the udpates I've done on it didn't change this variable (I do restart after every change to test).
Why is this happening? Do I have to set a PATH variable just for powershell?
The change might be "delayed", so try one or more of these solutions:
Log off and on again;
Task Manager > Restart "Windows Explorer" (explorer.exe)
Restart your launcher app (launchy, SlickRun, etc)
Reboot
Explanation:
Powershell will inherit the environment of the process that launched it (which depends on how you launch it). This is usually the interactive shell (explorer.exe). When you modify the environment from computer properties, you modify the environment of explorer.exe, so if you launch powershell from explorer.exe, (for example from the start menu) you should see the new environment.
However, if you launch it from something else (say a cmd.exe shell that you already had opened), then you won't since that process was launched under the old environment.
In other words: be careful how you are launching things.
In my case, I installed an app that incorrectly added itself to the PATH by creating a powershell profile that would override $env:PATH and blow out the existing configuration every time I started powershell.
Check if you have profile at USER\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1 and if it's doing anything fishy like setting $env:PATH.