Tag Archives: Set-Location

Push-Location’s Two for One

Sometimes, my life only has time for these short, little lessons.

Today, I learned something new, and without even thinking on it long, I went straight to my blog in order to share it. More or less, anyway. Before we get to the interesting part, let’s quickly discuss three PowerShell cmdlets: Set-Location, Push-Location, and Pop-Location.

Set-Location allows us to relocate ourselves within the file system. This is to say, that we can use this cmdlet to move around from folder to folder, and drive to drive. If I’m at the root of the C:\ drive, I can move to C:\Users, and if I’m in C:\Users and want to move to C:\Windows, I can also use Set-Location, or one of the aliases (cd, chdir, and sl), to get myself there. Here’s a quick example, before we move on.

PS C:\> Set-Location -Path C:\Users
PS C:\Users> Set-Location -Path C:\Windows
PS C:\Windows> Set-Location -Path \
PS C:\>

Push-Location’s purpose is to take our current location in the file system and add it to the location stack. We won’t delve into this too deeply, but picture it this way: It takes our current location in the file system — C:\, or C:\Users, or wherever — and puts it on a piece of paper, on top of a stack of other papers. Now we can reference our paper on top of the stack, to find our previous location the next time we need it.

And that, brings us to Pop-Location. Pop-Location gets the most recent entry on the location stack — that top piece of paper, if you will, and moves us to that location in the file system. Here’s an example of both Push-Location and Pop-Location.

PS C:\> # Our current location is the C:\ drive.
PS C:\> Push-Location
PS C:\> Set-Location -Path C:\Users
PS C:\Users> Pop-Location
PS C:\>

That introduction brings us to something I would’ve thought, I would have already known. Today I learned that Push-Location offers us a two-for-one. Not only will it place the current location on the location stack, as we’d expect, but it can also move us to a different location, such as Set-Location does. Watch.

PS C:\> # Back on the C:\ drive.
PS C:\> Push-Location -Path C:\Windows
PS C:\Windows> Pop-Location
PS C:\> Push-Location -Path C:\Users\tommymaynard
PS C:\Users\tommymaynard> Pop-Location
PS C:\>

With this tidbit of new information, I set out to replace the Set-Location cmdlet in my $PROFILE. Now when I use Set-Location — my new function — I’ll really be using Push-Location. Therefore, I can always return to the previous location in the filesystem with Pop-Location. Always.

Function Set-Location {
    Param (
       [string]$Path
    )
    Push-Location -Path $Path
}

PS C:\> # As you can see, I'm at the root of the C:\ drive.
PS C:\> Set-Location -Path C:\Windows
PS C:\Windows> Pop-Location
PS C:\>

Duplicate the Linux Prompt

I already have an answer to the question, “Why?” Because, I can. At some point in the last few days, I decided I would attempt to replicate the Linux prompt in PowerShell. So I did it, and I thought I would share it. I’ve broken this up a little with the full function toward the bottom of this evening’s post.

In this first section, we’ve created the prompt function’s basic structure and added our first bit of code. This code determines if the user that started the Windows PowerShell session is an administrator or not. If they are, they get the # symbol as part of the prompt, and if they’re not, they get the $ symbol.

Function Prompt {
    If ([bool](([System.Security.Principal.WindowsIdentity]::GetCurrent()).Groups -match 'S-1-5-32-544')) {
        $Symbol = '#'
    } Else {
        $Symbol = '$'
    }
}

The next addition includes the logic to determine how to write the path inside the prompt. If the current path is C:\Users\<CurrentUser>, it enters a tilde (~). If the path includes the C:\Users\<CurrentUser> path, in addition to one or more directories, it will enter a tilde and the other directory or directories, such as ~/Desktop, or ~/Favorites/Links. In the last case, it’ll simply list the current path after replacing the backslashes with forward slashes and dumping the drive letter and colon. In all instances, in fact, all (Windows) backslashes, will be replaced with (Unix/Linux) forward slashes.

Function Prompt {
    If ([bool](([System.Security.Principal.WindowsIdentity]::GetCurrent()).Groups -match 'S-1-5-32-544')) {
        $Symbol = '#'
    } Else {
        $Symbol = '$'
    }

    If ($PWD.Path -eq $env:USERPROFILE) {
        $Location = '~'
    } ElseIf ($PWD.Path -like "*$env:USERPROFILE*") {
        $Location = $PWD.Path -replace ($env:USERPROFILE -replace '\\','\\'),'~' -replace '\\','/'
    } Else {
        $Location = "$(($PWD.Path -replace '\\','/' -split ':')[-1])"
    }
}

The last section is where the prompt function actually writes the prompt to the screen. It’s the simple combination of the current user, an @ character, the computer name, the path, and the proper symbol (# or $). As you may notice, I’ve written the code to force the case of the current user and computer to lowercase.

Function Prompt {
    If ([bool](([System.Security.Principal.WindowsIdentity]::GetCurrent()).Groups -match 'S-1-5-32-544')) {
        $Symbol = '#'
    } Else {
        $Symbol = '$'
    }

    If ($PWD.Path -eq $env:USERPROFILE) {
        $Location = '~'
    } ElseIf ($PWD.Path -like "*$env:USERPROFILE*") {
        $Location = $PWD.Path -replace ($env:USERPROFILE -replace '\\','\\'),'~' -replace '\\','/'
    } Else {
        $Location = "$(($PWD.Path -replace '\\','/' -split ':')[-1])"
    }

    "$($env:USERNAME.ToLower())@$($env:COMPUTERNAME.ToLower()) $Location $Symbol "
}

In closing, I’ve included a gif of the prompt and an example of moving though the directory structure. While I typically only use full cmdlet names in my posts, this example does include aliases for the Set-Location cmdlet (cd, sl, and even chdir). Due to this function being saved in my profile script, this prompt displays immediately when a new console is opened, and every time after that. As someone that’s written a few different prompt functions, this one’s a keeper. I already can’t imaging switching back. On that note, you might not want to test it out.

duplicate-the-linux-prompt01

tommymaynard@srv01 / # $PWD.Path
C:\
tommymaynard@srv01 / # cd C:\Windows\
tommymaynard@srv01 /Windows # cd .\System32\
tommymaynard@srv01 /Windows/System32 # chdir ..
tommymaynard@srv01 /Windows # chdir ..
tommymaynard@srv01 / # sl /users
tommymaynard@srv01 /users # sl /users/tommymaynard2 # Not my current user.
tommymaynard@srv01 /users/tommymaynard2 # cd ..
tommymaynard@srv01 /users # cd C:\Users\tommymaynard\ # My current user.
tommymaynard@srv01 ~ # cd .\Desktop\
tommymaynard@srv01 ~/Desktop # cd ..
tommymaynard@srv01 ~ # cd .\Favorites\Links\
tommymaynard@srv01 ~/Favorites/Links # sl /
tommymaynard@srv01 / # cd /users
tommymaynard@srv01 /users # chdir \
tommymaynard@srv01 / #

Update1: A day later and I still love my new PowerShell prompt. I’ve made a minor change, however. The last line in the function is now the following three lines. It stores the prompt in a variable called $Prompt, modifies the title of the window to the $Prompt value, and then writes the prompt. In the past my window’s title indicate the computer name. Now it indicates that information, as well as the current user, the location on the current drive, and whether or not I’m running the session as an administrator.

...
	$Prompt = "$($env:USERNAME.ToLower())@$($env:COMPUTERNAME.ToLower()) $Location $Symbol "
	$Host.UI.RawUI.WindowTitle = $Prompt
	$Prompt
}

Update2: It occurred to me today that by entering the tilde character, such as Set-Location -Path ~, it moves you to the location stored in the Home property of the FileSystem PSProvider. Because of this, I opted to add another line, just before the beginning of the prompt function. Setting this property to $env:USERPROFILE, allows me to quickly move to C:\Users\<CurrentUser>. I should note that this property is sometimes already set. In those cases, this is just a precaution that the ~ character will move you back home.

(Get-PSProvider -PSProvider FileSystem).Home = $env:USERPROFILE
Function Prompt {
...
}

In case you want to take this prompt function for a spin, and you do, here’s everything. Copy and paste it to your console and hit Enter a couple times and try it out. If you hate it, close and reopen the PowerShell console and it never existed. Cheers.

(Get-PSProvider -PSProvider FileSystem).Home = $env:USERPROFILE
Function Prompt {
    If ([bool](([System.Security.Principal.WindowsIdentity]::GetCurrent()).Groups -match 'S-1-5-32-544')) {
        $Symbol = '#'
    } Else {
        $Symbol = '$'
    }
 
    If ($PWD.Path -eq $env:USERPROFILE) {
        $Location = '~'
    } ElseIf ($PWD.Path -like "*$env:USERPROFILE*") {
        $Location = $PWD.Path -replace ($env:USERPROFILE -replace '\\','\\'),'~' -replace '\\','/'
    } Else {
        $Location = "$(($PWD.Path -replace '\\','/' -split ':')[-1])"
    }

	$Prompt = "$($env:USERNAME.ToLower())@$($env:COMPUTERNAME.ToLower()) $Location $Symbol "
	$Host.UI.RawUI.WindowTitle = $Prompt
	$Prompt
}

 

about_Profiles

This post is the help rewrite for about_Profiles. 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)

Once you start using your profile ($PROFILE), you’ll have a hard time not using it and not adding new things to it. When you have a profile (script), it runs each time you open a new Windows PowerShell session. My current profile does a number of things – it sets my location to the C:\ drive, sets various variables, set aliases, modifies the console’s window title, and creates several functions. Some of those functions allow me to connect remotely to Exchange servers, load the VMWare PowerCLI PSSnapin (without having to remember its name), use Wake-on-LAN to wake my home computer, and several others.

There are several different profiles based on the host and the user. To see your profile, type $PROFILE and press Enter in the console or Integrated-Scripting Environment (ISE). As seen in the example below, this will display the path to the profile. Line 1 is typed in the standard PowerShell console and Line 3 in the ISE.

PS C:\> $PROFILE
C:\Users\tommymaynard\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1
PS C:\> $PROFILE
C:\Users\tommymaynard\Documents\WindowsPowerShell\Microsoft.PowerShellISE_profile.ps1

There are more profiles than these two and they are active under different circumstances. To see all the profiles, pipe the $PROFILE variable to the Select-Object cmdlet with the wildcard character.

PS C:\> $PROFILE | Select-Object -Property *

AllUsersAllHosts       : C:\Windows\System32\WindowsPowerShell\v1.0\profile.ps1
AllUsersCurrentHost    : C:\Windows\System32\WindowsPowerShell\v1.0\Microsoft.PowerShell_profile.ps1
CurrentUserAllHosts    : C:\Users\tommymaynard\Documents\WindowsPowerShell\profile.ps1
CurrentUserCurrentHost : C:\Users\tommymaynard\Documents\WindowsPowerShell\Microsoft.PowerShell_profile.ps1
Length                 : 82

Based on the information on the left hand side, there are different profiles based on who is using what host. While it’s not recommended to modify the profiles in the System32 directory, you should be able to tell what these do. The one on line1 is run for any user, regardless of what host (console/ISE) they use. The second one on line 2 is for any user in the current host. The third is for the current user, me, in all the hosts, and the final one is for me in the current host. These last two are the one’s you can modify.

But just by having a path stored in $PROFILE, doesn’t actually mean the file, or profile, actually exists. Use the Test-Path cmdlet to determine if the file/profile exists.

PS C:\> Test-Path $PROFILE
False

If this returns False, then you do not have a profile and so it will need to be created. You can create this file but using the New-Item cmdlet.

PS C:\> New-Item -Type File -Path $PROFILE -Force

    Directory: C:\Users\tommymaynard\Documents\WindowsPowerShell

Mode                LastWriteTime     Length Name
----                -------------     ------ ----
-a---         8/20/2014  12:39 PM          0 Microsoft.PowerShell_profile.ps1

These two commands can be put together in an If-Else statement that will test for the file, and if not found, will create the file. Once you have a profile file created, you can open it up and start adding to it. Remember that every time you open the matching console, the profile script will run.

If (-not(Test-Path $PROFILE)) {
    New-Item -Type File -Path $PROFILE -Force
}

Here’s some quick examples of things that could be added to a profile. The first example  changes the prompt location from its default to the root of the C:\ drive.

Set-Location \

The next example sets aliases for c and gh. The first example, in line 1, will allow me to use the letter c to run the Clear-Host cmdlet and in line 2, will allow me to use the alias gh in place of typing out Get-Help.

Set-Alias -Name c -Value Clear-Host
Set-Alias -Name gh -Value Get-Help

These next example allow me to set variables inside my profile. This will allow me to use $DCs to return DC01, DC02, DC03, allow me to use $hosts to return the path of my hosts file, and allow me to return all my web and data servers by using the $AppServers variable. Noticed that $AppSevers is a mulit-dimentional array. Use $AppServers[0] to return the web servers and $AppServers[1] to return the data servers.

Set-Variable -Name DCs -Value 'DC01','DC02','DC03'
Set-Variable -Name hosts -Value "$env:SystemRoot\System32\drivers\etc\hosts"
Set-Variable -Name AppServers -Value @(('web01','web02','web03'),('data01','data02','data03'))

You can also create functions. This function allows me to type Add-VMC to load the VMware PSSnapin. For me, it’s easier to remember this short function name than remembering the PSSnapin name or having to type out Get-PSSnapin -Registered to find the name.

Function Add-VMC {
	Add-PSSnapin VMware.VimAutomation.Core
}

Start using your $PROFILE today and everything you can to help personalize your PowerShell experience. Keep in mind that profiles do not exist in remote sessions.

Learn More

This information, and more, is stored in the help file about_Profile 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 it’s own window, 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_variables
PS C:\> Get-Help about_variables -ShowWindow
PS C:\> Get-Help about_variables| clip
PS C:\> Notepad $PSHOME\en-us\about_Variables.help.txt