Powershell: how to execute command for a path containing Unicode characters?

Question

I'm trying to execute a command in Powershell 5.1, but it fails when the path contains Unicode characters.

For example:

(Get-Acl 'E:/test .txt').access

I'm running the command from Node.js:

let childProcess = require('child_process')
let testProcess = childProcess.spawn('powershell', [])
testProcess.stdin.setEncoding('utf-8')

testProcess.stdout.on('data', (data) => {
  console.log(data.toString())
})

testProcess.stdout.on('error', (error) => {
  console.log(error)
})

// This path is working, I get command output in the console:
// testProcess.stdin.write("(Get-Acl 'E:/test.txt').access\n");

// This path is not working. I get nothing in the console
testProcess.stdin.write("(Get-Acl 'E:/test .txt').access\n");

I cannot use Powershell 7 since I'm making a Node.js app that runs commands on the pre-installed Powershell

Update

This method seems to work:

childProcess.spawn(
  'powershell', 
  ['-Command', '(Get-Acl "E:/test .txt").access']
)

Answer 1

By using stdin input to provide your command to powershell.exe, the Windows PowerShell CLI, you're implicitly relying on the system's active OEM code page, because that is what the PowerShell CLI uses to decode input received via stdin.

• Unless you've explicitly opted into the still-in-beta Windows 10 feature that allows setting both legacy code pages - ANSI and OEM - to UTF-8, the OEM code page is a fixed single-byte encoding limited to 256 characters that lacks support for most Unicode characters, such as Code page 437 on US-English systems.

• Additionally, providing commands via stdin (which can explicitly be requested with -File -) unexpectedly makes PowerShell exhibit pseudo-interactive behavior, which interferes with command output. See GitHub issue #3223 and GitHub issue #15331 for a discussion of this problematic behavior.

By contrast, passing commands via the -c (-Command) CLI parameter fully supports Unicode, irrespective of the active OEM code page, so it is a simple alternative that bypasses your original problem; borrowing from your own update to your question:

childProcess.spawn(
  'powershell', 
  ['-NoProfile', '-Command', '(Get-Acl "E:/test .txt").access']
)

Note that I've added -NoProfile in order to make the invocation more predictable / speed it up, as this option suppresses loading of the profile files that are usually only relevant for interactive use.