PowerShell function $input parameters

Question

First, I'm just learning PowerShell, but I have programmed in many scripting languages. I'm writing a script to retrieve output from a command on a remote server and then check that output for the word "running". Right now it retrieves the output of the command, and I have it in my variable, `$data`. The problem is I'm putting it through my "clean_data" function, and it's not the same contents in the variables that I'm passing to the function. What I'm wondering is how on Earth does the output of the `$data` variable have one content when printed to screen, but when passed to a function and immediately printed have a new content? What am I missing? I just want to loop through the lines that were returned to see how many have "running" in them and print a nice error if there isn't. CODE (Partial: function and relevant code) ``` function clean_data($input) { Write-Output "Received data"$input Write-Output "Cleaning data" $output=@() foreach ($line in $input) { Write-Output "Looking at:…

Accepted Answer

Careful, `$input` is an automatic variable used by PowerShell to allow iteration over data passed into a function. Try this instead:

```
function clean_data($data) {
  Write-Verbose "Received data: $data"
  Write-Verbose "Cleaning data"
  $output = @()
  foreach ($line in $data) {
     Write-Verbose "Processing line: $line"
     if ($line -match 'running') {
          $output += $line
     }
   }
   $output
}
```

PowerShell function $input parameters

Solution

Problem