Tee-Object

Reference

Module:: Microsoft.PowerShell.Utility

Saves command output in a file or variable and also sends it down the pipeline.

Syntax

Tee-Object
   [-InputObject <PSObject>]
   [-FilePath] <String>
   [-Append]
   [[-Encoding] <Encoding>]
   [<CommonParameters>]

Tee-Object
   [-InputObject <PSObject>]
   -LiteralPath <String>
   [[-Encoding] <Encoding>]
   [<CommonParameters>]

Tee-Object
   [-InputObject <PSObject>]
   -Variable <String>
   [<CommonParameters>]

Description

The Tee-Object cmdlet redirects output, that is, it sends the output of a command in two directions (like the letter T). It stores the output in a file or variable and also sends it down the pipeline. If Tee-Object is the last command in the pipeline, the command output is displayed at the prompt.

Examples

Example 1: Output processes to a file and to the console

This example gets a list of the processes running on the computer and sends the result to a file. Because a second path is not specified, the processes are also displayed in the console.

Get-Process | Tee-Object -FilePath "C:\Test1\testfile2.txt"

Handles  NPM(K)    PM(K)      WS(K) VM(M)   CPU(s)    Id ProcessName
-------  ------    -----      ----- -----   ------    -- -----------
83       4     2300       4520    39     0.30    4032 00THotkey
272      6     1400       3944    34     0.06    3088 alg
81       3      804       3284    21     2.45     148 ApntEx
81       4     2008       5808    38     0.75    3684 Apoint
...

Example 2: Output processes to a variable and `Select-Object`

This example gets a list of the processes running on the computer, saves them to the $proc variable, and pipes them to Select-Object.

Get-Process notepad | Tee-Object -Variable proc | Select-Object processname,handles

ProcessName                              Handles
-----------                              -------
notepad                                  43
notepad                                  37
notepad                                  38
notepad                                  38

The Select-Object cmdlet selects the ProcessName and Handles properties. Note that the $proc variable includes the default information returned by Get-Process.

Example 3: Output system files to two log files

This example saves a list of system files in a two log files, a cumulative file and a current file.

Get-ChildItem -Path D: -File -System -Recurse |
  Tee-Object -FilePath "c:\test\AllSystemFiles.txt" -Append |
    Out-File c:\test\NewSystemFiles.txt

The command uses the Get-ChildItem cmdlet to do a recursive search for system files on the D: drive. A pipeline operator (|) sends the list to Tee-Object, which appends the list to the AllSystemFiles.txt file and passes the list down the pipeline to the Out-File cmdlet, which saves the list in the NewSystemFiles.txt file.

Example 4: Print output to console and use in the pipeline

This example gets the files in a folder, prints them to the console, then filters the files for those that have a defined front matter metadata block. Finally, it lists the names of the articles that have front matter.

$consoleDevice = if ($IsWindows) {
    '\\.\CON'
} else {
    '/dev/tty'
}
$frontMatterPattern = '(?s)^---(?<FrontMatter>.+)---'

$articles = Get-ChildItem -Path .\reference\7.4\PSReadLine\About\ |
    Tee-Object -FilePath $consoleDevice |
    Where-Object {
        (Get-Content $_ -Raw) -match $frontMatterPattern
    }

$articles.Name

Directory: C:\code\docs\PowerShell-Docs\reference\7.4\PSReadLine\About

Mode                 LastWriteTime         Length Name
----                 -------------         ------ ----
-a---          12/13/2022 11:37 AM            384 .markdownlint.yaml
-a---           4/25/2023 11:28 AM          40194 about_PSReadLine_Functions.md
-a---           4/25/2023 10:58 AM          10064 about_PSReadLine.md

about_PSReadLine_Functions.md
about_PSReadLine.md

The example sets the $consoleDevice variable to the value of the current terminal's console device. On Windows, you can write to the current console device by redirecting your output to the \\.\CON filepath. On non-Windows systems, you use the /dev/tty filepath.

Then it sets the $frontMatterPattern variable to a regular expression that matches when a string starts with three dashes (---) and has any content before another three dashes. When this pattern matches an article's content, the article has a defined front matter metadata block.

Next, the example uses Get-ChildItem to retrieve every file in the About folder. Tee-Object prints the piped results to the console using the FileName parameter. Where-Object filters the files by getting their content as a single string with the Raw parameter of Get-Content and comparing that string to $frontMatterPattern.

Finally, the example prints the names of the files in the folder that have a defined front matter metadata block.

Parameters

-Append

Indicates that the cmdlet appends the output to the specified file. Without this parameter, the new content replaces any existing content in the file without warning.

This parameter was introduced in Windows PowerShell 3.0.

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

-Encoding

Specifies the type of encoding for the target file. The default value is utf8NoBOM.

The acceptable values for this parameter are as follows:

ascii: Uses the encoding for the ASCII (7-bit) character set.
ansi: Uses the encoding for the for the current culture's ANSI code page. This option was added in PowerShell 7.4.
bigendianunicode: Encodes in UTF-16 format using the big-endian byte order.
oem: Uses the default encoding for MS-DOS and console programs.
unicode: Encodes in UTF-16 format using the little-endian byte order.
utf7: Encodes in UTF-7 format.
utf8: Encodes in UTF-8 format.
utf8BOM: Encodes in UTF-8 format with Byte Order Mark (BOM)
utf8NoBOM: Encodes in UTF-8 format without Byte Order Mark (BOM)
utf32: Encodes in UTF-32 format.

Beginning with PowerShell 6.2, the Encoding parameter also allows numeric IDs of registered code pages (like -Encoding 1251) or string names of registered code pages (like -Encoding "windows-1251"). For more information, see the .NET documentation for Encoding.CodePage.

Starting with PowerShell 7.4, you can use the Ansi value for the Encoding parameter to pass the numeric ID for the current culture's ANSI code page without having to specify it manually.

This parameter was introduced in PowerShell 7.2.

Note

UTF-7* is no longer recommended to use. As of PowerShell 7.1, a warning is written if you specify utf7 for the Encoding parameter.

Type:	Encoding
Accepted values:	ASCII, BigEndianUnicode, OEM, Unicode, UTF7, UTF8, UTF8BOM, UTF8NoBOM, UTF32
Position:	1
Default value:	UTF8NoBOM
Required:	False
Accept pipeline input:	False
Accept wildcard characters:	False

-FilePath

Specifies a file that this cmdlet saves the object to Wildcard characters are permitted, but must resolve to a single file.

Starting in PowerShell 7, when you specify the FilePath as \\.\CON on Windows or /dev/tty on non-Windows systems, the InputObject is printed in the console. Those file paths correspond to the current terminal's console device on the system, enabling you to print the InputObject and send it to the output stream with one command.

Type:	String
Aliases:	Path
Position:	0
Default value:	None
Required:	True
Accept pipeline input:	False
Accept wildcard characters:	True

-InputObject

Specifies the object to be saved and displayed. Enter a variable that contains the objects or type a command or expression that gets the objects. You can also pipe an object to Tee-Object.

When you use the InputObject parameter with Tee-Object, instead of piping command results to Tee-Object, the InputObject value is treated as a single object even if the value is a collection.

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

-LiteralPath

Specifies a file that this cmdlet saves the object to. Unlike FilePath, the value of the LiteralPath parameter is used exactly as it is typed. No characters are interpreted as wildcards. If the path includes escape characters, enclose it in single quotation marks. Single quotation marks tell PowerShell not to interpret any characters as escape sequences.

Type:	String
Aliases:	PSPath, LP
Position:	Named
Default value:	None
Required:	True
Accept pipeline input:	False
Accept wildcard characters:	False

-Variable

Specifies a variable that the cmdlet saves the object to. Enter a variable name without the preceding dollar sign ($).

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

Inputs

PSObject

You can pipe objects to this cmdlet.

Outputs

PSObject

This cmdlet returns the object that it redirects.

Notes

PowerShell includes the following aliases for Tee-Object:

Windows:
- tee

You can also use the Out-File cmdlet or the redirection operator, both of which save the output in a file but do not send it down the pipeline.

Beginning in PowerShell 6, Tee-Object uses BOM-less UTF-8 encoding when it writes to files. If you need a different encoding, use the Out-File cmdlet with the Encoding parameter.

مشاركة عبر

Tee-Object

Syntax

Description

Examples

Example 1: Output processes to a file and to the console

Example 2: Output processes to a variable and `Select-Object`

Example 3: Output system files to two log files

Example 4: Print output to console and use in the pipeline

Parameters

-Append

-Encoding

-FilePath

-InputObject

-LiteralPath

-Variable

Inputs

Outputs

Notes

الموارد الإضافية

مشاركة عبر

Tee-Object

Syntax

Description

Examples

Example 1: Output processes to a file and to the console

Example 2: Output processes to a variable and `Select-Object`

Example 3: Output system files to two log files

Example 4: Print output to console and use in the pipeline

Parameters

-Append

-Encoding

-FilePath

-InputObject

-LiteralPath

-Variable

Inputs

Outputs

Notes

Related Links

الموارد الإضافية