About pwsh

Short Description

Explains how to use the pwsh command-line interface. Displays the command-line parameters and describes the syntax.

Long Description

Syntax

pwsh[.exe]
   [[-File] <filePath> [args]]
   [-Command { - | <script-block> [-args <arg-array>]
                 | <string> [<CommandParameters>] } ]
   [-ConfigurationName <string>]
   [-CustomPipeName <string>]
   [-EncodedCommand <Base64EncodedCommand>]
   [-ExecutionPolicy <ExecutionPolicy>]
   [-InputFormat {Text | XML}]
   [-Interactive]
   [-NoExit]
   [-NoLogo]
   [-NonInteractive]
   [-NoProfile]
   [-OutputFormat {Text | XML}]
   [-SettingsFile <SettingsFilePath>]
   [-Version]
   [-WindowStyle <style>]
   [-WorkingDirectory <directoryPath>]

pwsh[.exe] -h | -Help | -? | /?

Parameters

All parameters are case-insensitive.

-File | -f

If the value of File is -, the command text is read from standard input. Running pwsh -File - without redirected standard input starts a regular session. This is the same as not specifying the File parameter at all.

This is the default parameter if no parameters are present but values are present in the command line. The specified script runs in the local scope ("dot-sourced"), so that the functions and variables that the script creates are available in the current session. Enter the script file path and any parameters. File must be the last parameter in the command, because all characters typed after the File parameter name are interpreted as the script file path followed by the script parameters.

Typically, the switch parameters of a script are either included or omitted. For example, the following command uses the All parameter of the Get-Script.ps1 script file: -File .\Get-Script.ps1 -All

In rare cases, you might need to provide a Boolean value for a switch parameter. To provide a Boolean value for a switch parameter in the value of the File parameter, Use the parameter normally followed immediately by a colon and the boolean value, such as the following: -File .\Get-Script.ps1 -All:$False.

Parameters passed to the script are passed as literal strings, after interpretation by the current shell. For example, if you are in cmd.exe and want to pass an environment variable value, you would use the cmd.exe syntax: pwsh -File .\test.ps1 -TestParam %windir%

In contrast, running pwsh -File .\test.ps1 -TestParam $env:windir in cmd.exe results in the script receiving the literal string $env:windir because it has no special meaning to the current cmd.exe shell. The $env:windir style of environment variable reference can be used inside a Command parameter, since there it is interpreted as PowerShell code.

Similarly, if you want to execute the same command from a Batch script, you would use %~dp0 instead of .\ or $PSScriptRoot to represent the current execution directory: pwsh -File %~dp0test.ps1 -TestParam %windir%. If you instead used .\test.ps1, PowerShell would throw an error because it cannot find the literal path .\test.ps1

When the script file terminates with an exit command, the process exit code is set to the numeric argument used with the exit command. With normal termination, the exit code is always 0.

Similar to -Command, when a script-terminating error occurs, the exit code is set to 1. However, unlike with -Command, when the execution is interrupted with Ctrl-C the exit code is 0.

-Command | -c

Executes the specified commands (and any parameters) as though they were typed at the PowerShell command prompt, and then exits, unless the NoExit parameter is specified.

The value of Command can be -, a script block, or a string. If the value of Command is -, the command text is read from standard input.

The Command parameter only accepts a script block for execution when it can recognize the value passed to Command as a ScriptBlock type. This is only possible when running pwsh from another PowerShell host. The ScriptBlock type may be contained in an existing variable, returned from an expression, or parsed by the PowerShell host as a literal script block enclosed in curly braces ({}), before being passed to pwsh.

pwsh -Command {Get-WinEvent -LogName security}

In cmd.exe, there is no such thing as a script block (or ScriptBlock type), so the value passed to Command will always be a string. You can write a script block inside the string, but instead of being executed it will behave exactly as though you typed it at a typical PowerShell prompt, printing the contents of the script block back out to you.

A string passed to Command is still executed as PowerShell code, so the script block curly braces are often not required in the first place when running from cmd.exe. To execute an inline script block defined inside a string, the call operator & can be used:

pwsh -Command "& {Get-WinEvent -LogName security}"

If the value of Command is a string, Command must be the last parameter for pwsh, because all arguments following it are interpreted as part of the command to execute.

When called from within an existing PowerShell session, the results are returned to the parent shell as deserialized XML objects, not live objects. For other shells, the results are returned as strings.

If the value of Command is -, the command text is read from standard input. You must redirect standard input when using the Command parameter with standard input. For example:

@'
"in"

"hi" |
  % { "$_ there" }

"out"
'@ | powershell -NoProfile -Command -

This example produces the following output:

in
hi there
out

The process exit code is determined by status of the last (executed) command within the script block. The exit code is 0 when $? is $true or 1 when $? is $false. If the last command is an external program or a PowerShell script that explicitly sets an exit code other than 0 or 1, that exit code is converted to 1 for process exit code. To preserve the specific exit code, add exit $LASTEXITCODE to your command string or script block.

Similarly, the value 1 is returned when a script-terminating (runspace-terminating) error, such as a throw or -ErrorAction Stop, occurs or when execution is interrupted with Ctrl-C.

-ConfigurationName | -config

Specifies a configuration endpoint in which PowerShell is run. This can be any endpoint registered on the local machine including the default PowerShell remoting endpoints or a custom endpoint having specific user role capabilities.

Example: pwsh -ConfigurationName AdminRoles

-CustomPipeName

Specifies the name to use for an additional IPC server (named pipe) used for debugging and other cross-process communication. This offers a predictable mechanism for connecting to other PowerShell instances. Typically used with the CustomPipeName parameter on Enter-PSHostProcess.

This parameter was introduced in PowerShell 6.2.

For example:

# PowerShell instance 1
pwsh -CustomPipeName mydebugpipe
# PowerShell instance 2
Enter-PSHostProcess -CustomPipeName mydebugpipe

-EncodedCommand | -e | -ec

Accepts a Base64-encoded string version of a command. Use this parameter to submit commands to PowerShell that require complex, nested quoting. The Base64 representation must be a UTF-16 encoded string.

For example:

$command = 'dir "c:\program files" '
$bytes = [System.Text.Encoding]::Unicode.GetBytes($command)
$encodedCommand = [Convert]::ToBase64String($bytes)
pwsh -encodedcommand $encodedCommand

-ExecutionPolicy | -ex | -ep

Sets the default execution policy for the current session and saves it in the $env:PSExecutionPolicyPreference environment variable. This parameter does not change the persistently configured execution policies.

This parameter only applies to Windows computers. The $env:PSExecutionPolicyPreference environment variable does not exist on non-Windows platforms.

-InputFormat | -in | -if

Describes the format of data sent to PowerShell. Valid values are "Text" (text strings) or "XML" (serialized CLIXML format).

-Interactive | -i

Present an interactive prompt to the user. Inverse for NonInteractive parameter.

-NoExit | -noe

Does not exit after running startup commands.

Example: pwsh -NoExit -Command Get-Date

-NoLogo | -nol

Hides the copyright banner at startup of interactive sessions.

-NonInteractive | -noni

Does not present an interactive prompt to the user. Any attempts to use interactive features, like Read-Host or confirmation prompts, result in statement-terminating errors.

-NoProfile | -nop

Does not load the PowerShell profiles.

-OutputFormat | -o | -of

Determines how output from PowerShell is formatted. Valid values are "Text" (text strings) or "XML" (serialized CLIXML format).

Example: pwsh -o XML -c Get-Date

When called withing a PowerShell session, you get deserialized objects as output rather plain strings. When called from other shells, the output is string data formatted as CLIXML text.

-SettingsFile | -settings

Overrides the system-wide powershell.config.json settings file for the session. By default, system-wide settings are read from the powershell.config.json in the $PSHOME directory.

Note that these settings are not used by the endpoint specified by the -ConfigurationName argument.

Example: pwsh -SettingsFile c:\myproject\powershell.config.json

-SSHServerMode | -sshs

Used in sshd_config for running PowerShell as an SSH subsystem. It is not intended or supported for any other use.

-Version | -v

Displays the version of PowerShell. Additional parameters are ignored.

-WindowStyle | -w

Sets the window style for the session. Valid values are Normal, Minimized, Maximized and Hidden.

-WorkingDirectory | -wd

Sets the initial working directory by executing at startup. Any valid PowerShell file path is supported.

To start PowerShell in your home directory, use: pwsh -WorkingDirectory ~

-Help, -?, /?

Displays help for pwsh. If you are typing a pwsh command in PowerShell, prepend the command parameters with a hyphen (-), not a forward slash (/).