Tag Archives: Get-Content

What PowerShell Modules does the RSAT Provide (on Windows 8.1)

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I built a new Windows 8.1 machine recently, and as we all know, doing that requires new software installations. In my case, that included the RSAT. The RSAT, or Remote Server Administration Tools, allow IT admins the ability to remotely manage features on Windows Server operating systems from a client operating system—here’s a link to the RSAT for Windows 8.1.

Prior to running the RSAT installer, I wanted to collect the currently available Windows PowerShell modules that I already had on my computer. This would allow me to know exactly what modules were added after the RSAT installer finished. The command below collects all the modules, returns only their name, and then drops that into a file on my computer. We’ll use the file in a moment, as part of a comparison.

PS C:\> Get-Module -ListAvailable | Select-Object -ExpandProperty Name | Out-File C:\Users\tommymaynard\Pre-RSAT-PowerShell-Modules.txt

I verified the file contained the module names by using the Get-Content cmdlet. In addition, I ran a slightly modified command to get the item count in the file—both can be seen below. The output created by the first command has been truncated to save space.

PS C:\> Get-Content C:\Users\tommymaynard\Pre-RSAT-PowerShell-Modules.txt
AppBackgroundTask
AppLocker
Appx
AssignedAccess
...
PS C:\> (Get-Content C:\Users\tommymaynard\Pre-RSAT-PowerShell-Modules.txt).Count
57

Once this file was in placed, and I was satisfied that it contained what I wanted, I went ahead with the RSAT install. Upon completion, I reran the Get-Module command above, after modifying the name of the file it would create (pre vs. post). I then read in the contents of the new file (which has been truncated again), and checked the number of modules listed in the file. There were now 75 modules where there had only been 57 before the RSAT install.

PS C:\> Get-Module -ListAvailable | Select-Object -ExpandProperty Name | Out-File C:\Users\tommymaynard\Post-RSAT-PowerShell-Modules.txt
PS C:\> Get-Content C:\Users\tommymaynard\Post-RSAT-PowerShell-Modules.txt
ActiveDirectory
AppBackgroundTask
AppLocker
Appx
...
PS C:\> (Get-Content C:\Users\tommymaynard\Post-RSAT-PowerShell-Modules.txt).Count
75

Knowing that there’s 18 new modules is helpful, but which ones were added? The Compare-Object cmdlet can tell us. As seen below, we have the cmdlet read in the lines of each file and then determine which ones aren’t included in both files.

PS C:\> Compare-Object -ReferenceObject (Get-Content C:\Users\tommymaynard\Desktop\Pre-RSAT-PowerShell-Modules.txt) -DifferenceObject (Get-Content C:\Users\tommymaynard\Desktop\Post-RSAT-PowerShell-Modules.txt)

InputObject                                                 SideIndicator
-----------                                                 -------------
ActiveDirectory                                             =>
BestPractices                                               =>
ClusterAwareUpdating                                        =>
DFSN                                                        =>
DFSR                                                        =>
DhcpServer                                                  =>
DnsServer                                                   =>
FailoverClusters                                            =>
GroupPolicy                                                 =>
IpamServer                                                  =>
IscsiTarget                                                 =>
NetworkLoadBalancingClusters                                =>
NFS                                                         =>
RemoteAccess                                                =>
RemoteDesktop                                               =>
ServerManager                                               =>
ServerManagerTasks                                          =>
UpdateServices                                              =>

As we can see above, our Compare-Object results indicate that the difference object (the post file, or the file on the right) has new modules—now we know which ones were added since installing the RSAT.

about_Aliases

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This post is the help rewrite for about_Aliases. While the help files for Windows PowerShell are invaluable, the idea behind a rewrite is so true beginners might even better understand the help file concepts. At times, some things discussed in the Windows PowerShell help file will not be included in a help rewrite. Therefore, it is always best to read the actual help file after reading this post. (PS3.0)

An Alias in Windows PowerShell is a simplified, or quicker, way to type a cmdlet using an alternate name. Get-Alias (or the alias for Get-Alias, gal) will display a list of all of the aliases that the Windows PowerShell session knows about. This includes both built-in aliases and any additional aliases created or imported. The first two examples below, indicate two ways to accomplish the same thing–listing all the aliases. These examples only show the first four results.

PS C:\> Get-Alias

CommandType     Name                                               ModuleName
-----------     ----                                               ----------
Alias           % -> ForEach-Object
Alias           ? -> Where-Object
Alias           ac -> Add-Content
Alias           asnp -> Add-PSSnapin

This example uses the alias for the Get-Alias cmdlet, gal.

PS C:\> gal

CommandType     Name                                               ModuleName
-----------     ----                                               ----------
Alias           % -> ForEach-Object
Alias           ? -> Where-Object
Alias           ac -> Add-Content
Alias           asnp -> Add-PSSnapin

To find the cmdlet associated with a single alias, the alias needs to be provided, as the value for the -Name parameter, to the Get-Alias cmdlet.

PS C:\> gal -Name gc

CommandType     Name                                               ModuleName
-----------     ----                                               ----------
Alias           gc -> Get-Content

The name parameter (-Name) is not required to use it. This means that if there is something after the Get-Alias cmdlet, such as gc in this example, then it will default to using the -Name parameter.

PS C:\> gal gc

CommandType     Name                                               ModuleName
-----------     ----                                               ----------
Alias           gc -> Get-Content

Windows PowerShell will error if the -Name parameter is supplied with a cmdlet name or another value that is not an alias.

PS C:\> gal Get-Content
gal : This command cannot find a matching alias because an alias with the name ‘Get-Content’ does not exist.
At line:1 char:1
+ gal Get-Content
+ ~~~~~~~~~~~~~~~
+ CategoryInfo          : ObjectNotFound: (Get-Content:String) [Get-Alias], ItemNotFoundException
+ FullyQualifiedErrorId : ItemNotFoundException,Microsoft.PowerShell.Commands.GetAliasCommand

In order to get an alias (or aliases, if there is more than one) for a cmdlet, the -Definition parameter must be used.

PS C:\> gal -Definition Get-Content

CommandType     Name                                               ModuleName
-----------     ----                                               ----------
Alias           cat -> Get-Content
Alias           gc -> Get-Content
Alias           type -> Get-Content

The Get-Service cmdlet returns the computer’s services, the Get-Process cmdlet returns the processes running on the computer, and the Get-ChildItem cmdlet returns the directories and/or files from the root of a drive or from a folder. Here is how a user can get the aliases for multiple cmdlets at the same time.

PS C:\> gal -Definition Get-Service,Get-Process,Get-ChildItem

CommandType     Name                                               ModuleName
-----------     ----                                               ----------
Alias           gsv -> Get-Service
Alias           gps -> Get-Process
Alias           ps -> Get-Process
Alias           dir -> Get-ChildItem
Alias           gci -> Get-ChildItem
Alias           ls -> Get-ChildItem

There are a few other cmdlets that allow a user to work with aliases. By using the Get-Command cmdlet (or its alias–if it has one), additional cmdlets can be returned that all end with -Alias.

PS C:\> Get-Command *-Alias

CommandType     Name                                               ModuleName
-----------     ----                                               ----------
Cmdlet          Export-Alias                                       Microsoft.PowerShell.Utility
Cmdlet          Get-Alias                                          Microsoft.PowerShell.Utility
Cmdlet          Import-Alias                                       Microsoft.PowerShell.Utility
Cmdlet          New-Alias                                          Microsoft.PowerShell.Utility
Cmdlet          Set-Alias                                          Microsoft.PowerShell.Utility

Export-Alias: Exports information about currently defined aliases to a file.

PS C:\> Export-Alias -Path 'C:\aliases.txt'

Import-Alias: Imports an alias, or aliases, from a file.

PS C:\> Import-Alias -Path 'C:\ImportedAliases.txt'

Trying to import aliases that already exist will cause an error for every alias Windows PowerShell tries to import (that already exists).

PS C:\> Export-Alias -Path 'C:\aliases.txt'
PS C:\> Import-Alias -Path 'C:\aliases.txt'
Import-Alias : The alias is not allowed, because an alias with the name ‘ac’ already exists.
At line:1 char:1
+ Import-Alias -Path ‘C:\aliases.txt’
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : ResourceExists: (ac:String) [Import-Alias], SessionStateException
    + FullyQualifiedErrorId : AliasAlreadyExists,Microsoft.PowerShell.Commands.ImportAliasCommand

New-Alias: Creates a new alias.
Set-Alias: Changes an existing alias, or creates an alias if it does not already exist.

PS C:\> New-Alias -Name MyAlias -Value Get-Process
PS C:\> MyAlias | select -First 4

Handles  NPM(K)    PM(K)      WS(K) VM(M)   CPU(s)     Id ProcessName
-------  ------    -----      ----- -----   ------     -- -----------
    224      19     3440        772   110    16.50   4612 ALMon
    164      14     2476       2108    44     5.36   2744 ALsvc
     77       9     1336       5288    75   137.55   4076 ApMsgFwd
     90       8     1372       5788    76   162.11   4324 ApntEx

PS C:\> Set-Alias -Name MyAlias -Value Get-Service
PS C:\> MyAlias | select -First 4

Status   Name               DisplayName
------   ----               -----------
Running  AdobeARMservice    Adobe Acrobat Update Service
Stopped  AdobeFlashPlaye... Adobe Flash Player Update Service
Stopped  AeLookupSvc        Application Experience
Stopped  ALG                Application Layer Gateway Service

Bonus Information

Use the Measure-Object cmdlet, or the count property, to find out how many aliases Windows PowerShell knows about.

PS C:\> Get-Alias | Measure-Object

Count    : 182
Average  :
Sum      :
Maximum  :
Minimum  :
Property :

PS C:\> gal | measure

Count    : 182
Average  :
Sum      :
Maximum  :
Minimum  :
Property :

PS C:\> (gal | measure).count
182
PS C:\> (gal).count
182

Real World

While aliases are helpful in the console, the belief is that they should not be used in a script file (.ps1 file). Using full cmdlet names in a script is preferred for script readability. There are plenty of people writing Windows PowerShell who adhere to this best practice even while using aliases for the object cmdlets (select for Select-Object, where for Where-Object, etc.).

Learn More

This information, and more, are stored in the help file about_Aliases that comes with Windows PowerShell. This information can be read by typing any of the commands below. The first example will display the help file in the Windows PowerShell console, the second example will open the full help in its own window, and the third example will send the contents of the help file to the clipboard (so it can be pasted into Word, Notepad, etc.), and the fourth example will open the help file in Notepad.

PS C:\> Get-Help about_aliases
PS C:\> Get-Help about_aliases -ShowWindow
PS C:\> Get-Help about_aliases | clip
PS C:\> Notepad C:\Windows\System32\WindowsPowerShell\v1.0\en-US\about_Aliases.help.txt

There is a built-in, automatic variable $PSHOMEthat stores the installation path of Windows PowerShell. This means that the third example above could have been partially written using that variable.

PS C:\> Notepad $PSHOME\en-us\about_Aliases.help.txt