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Clear-History

  • Reference
Module:
Microsoft.PowerShell.Core

Deletes entries from the PowerShell session command history.

Syntax

Clear-History
     [[-Id] <int[]>]
     [[-Count] <int>]
     [-Newest]
     [-WhatIf]
     [-Confirm]
     [<CommonParameters>]
Clear-History
     [[-Count] <int>]
     [-CommandLine <string[]>]
     [-Newest]
     [-WhatIf]
     [-Confirm]
     [<CommonParameters>]

Description

Clear-History deletes the command history from a PowerShell session. Each PowerShell session has its own command history. To display the command history, use the Get-History cmdlet.

By default, Clear-History deletes the entire command history from a PowerShell session. You can use parameters with Clear-History to delete selected commands.

Clear-History does not clear the PSReadLine command history file. The PSReadLine module stores a history file that contains every PowerShell command from every PowerShell session. From a PowerShell prompt, use the up and down arrows on your keyboard to scroll through the command history. To display the PSReadLine configuration for command history, use Get-PSReadLineOption. PSReadLine shipped with PowerShell 5.0 and above. For more information, see about_PSReadLine.

Examples

Example 1: Delete the command history from a PowerShell session

This command deletes all of the commands from a PowerShell session's history.

Get-History

Id CommandLine
  -- -----------
   1 Set-Location .\Test
   2 Update-Help
   3 Set-Location C:\Test\Logs
   4 Get-Location

Clear-History
Get-History

Id CommandLine
  -- -----------
   5 Clear-History

The Get-History cmdlet displays the PowerShell session's history. Clear-History deletes the entire command history. Get-History displays the updated command history and confirms the prior history was deleted.

Example 2: Delete the newest commands

This command uses the Count and Newest parameters to delete the newest commands from a PowerShell session's history.

Get-History

Id CommandLine
  -- -----------
   1 Set-Location C:\Test\
   2 Get-Command Clear-History
   3 Get-Command Clear-History -Syntax
   4 Get-Command Clear-History -ShowCommandInfo
   5 Get-Help Get-Alias
   6 Get-Command Get-ChildItem -Syntax
   7 Get-Help Clear-History
   8 Set-Location C:\Test\Logs
   9 Get-Help Get-Variable
  10 Get-Help Get-ChildItem

Clear-History -Count 5 -Newest
Get-History

Id CommandLine
  -- -----------
   1 Set-Location C:\Test\
   2 Get-Command Clear-History
   3 Get-Command Clear-History -Syntax
   4 Get-Command Clear-History -ShowCommandInfo
   5 Get-Help Get-Alias
  11 Clear-History -Count 5 -Newest

The Get-History cmdlet displays the PowerShell session's history. Clear-History is used to delete the command history. The Count parameter specifies the number of commands to delete, inclusive of the specified Id. The Newest parameter specifies that the newest commands are cleared from the history. Get-History displays the updated command history and confirms that the five newest commands were deleted, Id 6 - Id 10.

Example 3: Delete commands that match specific criteria

This command deletes commands that match specific criteria defined by the CommandLine parameter.

Get-History

Id CommandLine
  -- -----------
   1 Set-Location C:\Test\
   2 Get-Command Clear-History
   3 Get-Command Clear-History -Syntax
   4 Get-Command Clear-History -ShowCommandInfo
   5 Get-Help Get-Alias
   6 Get-Command Get-ChildItem -Syntax
   7 Get-Help Clear-History

Clear-History -CommandLine *Help*, *Syntax
Get-History

Id CommandLine
  -- -----------
   1 Set-Location C:\Test\
   2 Get-Command Clear-History
   4 Get-Command Clear-History -ShowCommandInfo
   8 Clear-History -CommandLine *Help*, *Syntax

The Get-History cmdlet displays the PowerShell session's history. Clear-History deletes the command history. The CommandLine parameter specifies commands that contain Help or end with Syntax. Get-History displays the updated command history and confirms that commands Id 3, Id 5, Id 6, and Id 7 were deleted.

Example 4: Delete commands by Id number

This command deletes specific history items using the Id. To delete multiple commands, submit a comma-separated list of Id numbers.

Get-History

Id CommandLine
  -- -----------
   1 Set-Location C:\Test\
   2 Get-History
   3 Get-Help Get-Alias
   4 Get-Command Clear-History
   5 Get-Command Clear-History -Syntax
   6 Get-Command Clear-History -ShowCommandInfo

Clear-History -Id 3, 5
Get-History

Id CommandLine
  -- -----------
   1 Set-Location C:\Test\
   2 Get-History
   4 Get-Command Clear-History
   6 Get-Command Clear-History -ShowCommandInfo
   7 Get-History
   8 Clear-History -Id 3, 5

The Get-History cmdlet displays the PowerShell session's history. Clear-History deletes the command history. The Id parameter specifies which commands to delete. Get-History displays the updated command history and confirms that Id 3 and Id 5 were deleted.

Example 5: Delete commands by Id number and count

This command uses the Id and Count parameters to delete command history. Commands are deleted from the specified Id in reverse order, newest to oldest.

Get-History

Id CommandLine
  -- -----------
   1 Set-Location C:\Test\
   2 Get-Command Clear-History
   3 Get-Command Clear-History -Syntax
   4 Get-Command Clear-History -ShowCommandInfo
   5 Get-Help Get-Alias
   6 Get-Command Get-ChildItem -Syntax
   7 Get-Help Clear-History
   8 Set-Location C:\Test\Logs
   9 Get-Help Get-Variable
  10 Get-Help Get-ChildItem

Clear-History -Id 7 -Count 5
Get-History

Id CommandLine
  -- -----------
   1 Set-Location C:\Test\
   2 Get-Command Clear-History
   8 Set-Location C:\Test\Logs
   9 Get-Help Get-Variable
  10 Get-Help Get-ChildItem
  11 Clear-History -Id 7 -Count 5

The Get-History cmdlet displays the PowerShell session's history. Clear-History deletes the command history. The Id parameter specifies to begin with Id 7. The Count parameter specifies to delete five commands, inclusive of the specified Id. Get-History displays the updated command history and confirms that five commands were deleted, Id 3 - Id 7.

Parameters

-CommandLine

Deletes command history from a PowerShell session. The string must be an exact match or use wildcards to match commands in the PowerShell session history displayed by Get-History. If you enter more than one string, Clear-History deletes commands that match any of the strings. The CommandLine parameter can be used with Count.

For strings with a space, use single quotations. For more information, see about_Quoting_Rules.

Type:String[]
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:True

-Confirm

Prompts you for confirmation before running the Clear-History cmdlet.

Type:SwitchParameter
Aliases:cf
Position:Named
Default value:False
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Count

Specifies the number of history entries that Clear-History deletes. Commands are deleted in order, beginning with the oldest entry in the history.

The Count and Id parameters can be used together. The Count parameter specifies the number of commands to delete, inclusive of the specified Id. Beginning at the specified Id, commands are deleted in reverse sequential order. For example, if the Id is 30 and the Count is 10, Clear-History deletes items 21 through 30.

The Count and CommandLine parameters can be used together. Count specifies the number of commands to delete that match CommandLine parameter value. The commands are deleted in sequential order.

Type:Int32
Position:1
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Id

Specifies the command history Id that Clear-History deletes. To display Id numbers, use the Get-History cmdlet. The Id numbers are sequential and commands keep their Id number throughout a PowerShell session. The Id parameter can be used with Count and Newest.

Type:Int32[]
Position:0
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-Newest

When the Newest parameter is used, Clear-History deletes the newest entries in the history. By default, Clear-History deletes the oldest entries in the history.

The Newest parameter can be used with Id and Count. The Count parameter specifies the number of commands to delete, inclusive of the specified Id. Beginning at the specified Id, commands are deleted in sequential order. For example, if the Id is 30 and the Count is 10, Clear-History deletes items 30 through 39.

Type:SwitchParameter
Position:Named
Default value:None
Required:False
Accept pipeline input:False
Accept wildcard characters:False

-WhatIf

Shows what would happen if the Clear-History cmdlet runs. The cmdlet is not run.

Type:SwitchParameter
Aliases:wi
Position:Named
Default value:False
Required:False
Accept pipeline input:False
Accept wildcard characters:False

Inputs

None

You can't pipe objects to this cmdlet.

Outputs

None

This cmdlet returns no output.

Notes

PowerShell includes the following aliases for Clear-History:

  • All platforms:
    • clhy

The PowerShell session history is a list of the commands entered during a PowerShell session. You can view the history, add and delete commands, and run commands from the history. For more information, see about_History.

The session history is managed separately from the history maintained by the PSReadLine module. Both histories are available in sessions where PSReadLine is loaded. This cmdlet only works with the session history. For more information see, about_PSReadLine.