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How do I run multiple commands on one line in PowerShell?

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Chapters
00:00 How Do I Run Multiple Commands On One Line In Powershell?
00:32 Accepted Answer Score 788
00:42 Answer 2 Score 63
01:50 Answer 3 Score 37
02:33 Answer 4 Score 14
04:01 Thank you

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Full question
https://superuser.com/questions/612409/h...

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Content licensed under CC BY-SA
https://meta.stackexchange.com/help/lice...

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Tags
#windows #commandline #powershell

#avk47



ACCEPTED ANSWER

Score 788


Use a semicolon to chain commands in PowerShell:

ipconfig /release; ipconfig /renew



ANSWER 2

Score 63


In PowerShell 7, we have Pipeline chain operators which allows you to add some conditional element to your sequential one-line commands

The operators are:

  • && this will run the second command only if the first one succeeds.
  • || this will run the second command only if the first one fails.

examples:

C:\> Write-Host "This will succeed" && Write-Host "So this will run too"
This will succeed
So this will run too

C:\> Write-Error "This is an error" && Write-Host "So this shouldn't run"
Write-Error "This is an error" && Write-Host "So this shouldn't run": This is an error

C:\> Write-Host "This will succeed" || Write-Host "This won't run"
This will succeed

C:\> Write-Error "This is an error" || Write-Host "That's why this runs"
Write-Error "This is an error" || Write-Host "That's why this runs" 
This is an error
That's why this runs

of course you can chain them even more together like x && y || z etc.

this also works for old cmd-like commands like ipconfig

> ipconfig && Write-Error "abc" || ipconfig


Windows-IP-Konfiguration


Ethernet-Adapter Ethernet:

   Verbindungsspezifisches DNS-Suffix: xxx
   Verbindungslokale IPv6-Adresse  . : xxx
   IPv4-Adresse  . . . . . . . . . . : xxx
   Subnetzmaske  . . . . . . . . . . : 255.255.255.0
   Standardgateway . . . . . . . . . : xxx
ipconfig && Write-Error "abc" || ipconfig: abc

Windows-IP-Konfiguration


Ethernet-Adapter Ethernet:

   Verbindungsspezifisches DNS-Suffix: xxx
   Verbindungslokale IPv6-Adresse  . : xxx
   IPv4-Adresse  . . . . . . . . . . : xxx
   Subnetzmaske  . . . . . . . . . . : 255.255.255.0
   Standardgateway . . . . . . . . . : xxx

These operators use the $? and $LASTEXITCODE variables to determine if a pipeline failed. This allows you to use them with native commands and not just with cmdlets or functions.

Source: https://docs.microsoft.com/en-us/powershell/scripting/whats-new/what-s-new-in-powershell-70?view=powershell-7




ANSWER 3

Score 37


A semicolon will link the commands as the previous answer stated, although there is a key difference to the behaviour with the & operator in the MS-DOS style command interpreter.

In the command interpreter, the variable substitution takes place when the line is read. This allows some neat possibilities such as swapping variables without an interim:

set a=1
set b=2
set a=%b% & set b=%a%
echo %a%
echo %b%

Would result in:

2
1

As far as I know, there is no way to replicate this behaviour in PowerShell. Some may argue that's a good thing.

There is in fact a way to do this in PowerShell:

$b, $a = $a, $b

It will result in a single line swapping of the variable values.




ANSWER 4

Score 14


For PowerShell 5 (default install for Windows machines for the foreseeable future), you can of course use a semicolon to separate statements, but all statements will be executed by default even if one fails. Personally, I prefer to run things so that if one thing fails the whole line stops in the REPL and I imagine a lot of other folks do as well.

$ErrorActionPreference lets you control the behavior of what happens when a statement fails but is a non-terminating error (which are most errors including command not found errors). You can set this variable $ErrorActionPreference="Stop" in order to emulate the behavior of && in Bash and PowerShell 7 for the scope of this variable.

$ErrorActionPreference="Stop"
# Line break
fakeCommand; echo "Here"

I have had trouble finding precise documentation for this behavior, but this variable seems to be dynamically scoped so you can override it in a block temporarily if you don't want to set it globally.

Invoke-Command -ScriptBlock {$ErrorActionPreference="Stop"; fakeCommand; echo "Here"}

Finally, if you want something reusable, you can use this higher order function.

function Run-Block-With-Error($block) {
    $ErrorActionPreference="Stop"
    Invoke-Command -ScriptBlock $block
}

Which is then used as follows.

Run-Block-With-Error {fakeCommand; echo "Here"}

Note in the examples above that "Here" is not printed since fakeCommand fails as it is not a real command.

I have tested the code provided in this solution for both PowerShell 5 and 7 and it should be fully portable, at least on Windows. While PowerShell 7 should be very similar on different platforms, I did not test these commands on Linux or MacOS.