Determine the OS version, Linux and Windows from Powershell

Aren't there environment variables you can view on the other platforms for the OS?

Get-ChildItem -Path Env:

Particularly, on Windows at least, there's an OS environment variable, so you should be able to accomplish this by using $Env:OS.

Since some time has passed and the PowerShell Core (v6) product is GA now (the Core branding has been dropped as of v7), you can more accurately determine your platform based on the following automatic boolean variables:

$IsMacOS$IsLinux$IsWindows

Since the PowerShell versions 6.1 on Windows/Linux/OSX went to GA you can use the new properties of $PSVersionTable, OS, Platform and GitCommitId

Update In v6.0.0-beta.3 there are some breaking changes:

• Change positional parameter for powershell.exe from -Command to -File

$PSVersionTable on :

Platform Win32NT OS Microsoft Windows 10.0.15063

PS C:\Users\LotPings> $PSVersionTableName                           Value----                           -----PSVersion                      6.1.0PSEdition                      CoreGitCommitId                    6.1.0OS                             Microsoft Windows 10.0.17134Platform                       Win32NTPSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}PSRemotingProtocolVersion      2.3SerializationVersion           1.1.0.1WSManStackVersion              3.0

Platform Unix OS Linux (ubuntu)

PS /home/LotPings> $PSVersionTableName                           Value----                           -----PSVersion                      6.1.0PSEdition                      CoreGitCommitId                    6.1.0OS                             Linux 4.15.0-34-generic #37-Ubuntu SMP Mon Aug 27 15:21:48 UTC 2018Platform                       UnixPSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}PSRemotingProtocolVersion      2.3SerializationVersion           1.1.0.1WSManStackVersion              3.0

Platform Unix OS Darwin

PS /Users/LotPings> $PSVersionTableName                           Value----                           -----PSVersion                      6.1.0PSEdition                      CoreGitCommitId                    6.1.0OS                             Darwin 17.7.0 Darwin Kernel Version 17.7.0: Thu Jun 21 22:53:14 PDT 2018; root:xnu-4570.71.2~1/RE...Platform                       UnixPSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}PSRemotingProtocolVersion      2.3SerializationVersion           1.1.0.1WSManStackVersion              3.0

For PowerShell Core (Powershell Version 6.0+), you can use Automatic Variables: $IsLinux, $IsMacOS and $IsWindows.

For example,

if ($IsLinux) {    Write-Host "Linux"}elseif ($IsMacOS) {    Write-Host "macOS"}elseif ($IsWindows) {    Write-Host "Windows"}