Functions/GenXdev.Windows/Get-OpenedFileHandleProcesses.ps1

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<#
.SYNOPSIS
Retrieves processes that have open file handles to specified files.
 
.DESCRIPTION
Uses the Sysinternals handle.exe tool to identify processes that currently have
open handles to one or more specified files. This is useful for determining
which processes are preventing file operations like deletion or modification.
 
The function requires handle.exe from the Sysinternals suite to be installed
and available in the system path. It parses the output from handle.exe to
identify processes with open handles to the specified files and returns
detailed information about those processes.
 
.PARAMETER FilePath
The path to the file(s) to check for open handles. Supports pipeline input.
Multiple file paths can be provided to check multiple files at once.
 
.EXAMPLE
Get-OpenedFileHandleProcesses -FilePath "C:\temp\example.txt"
# Identifies all processes that have open handles to the specified file
 
.EXAMPLE
"file1.txt", "file2.txt" | Get-OpenedFileHandleProcesses
# Checks multiple files via pipeline input for processes with open handles
#>

function Get-OpenedFileHandleProcesses {


    [CmdletBinding()]
    [System.Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSUseSingularNouns", "")]
    param(
        ########################################################################
        [Parameter(
            Mandatory = $true,
            Position = 0,
            ValueFromPipeline = $true,
            ValueFromPipelineByPropertyName = $true,
            HelpMessage = "The path to the file(s) to check for open handles"
        )]
        [ValidateNotNullOrEmpty()]
        [string[]]$FilePath
        ########################################################################
    )

    begin {

        # log start of process detection for user visibility
        Microsoft.PowerShell.Utility\Write-Verbose "Starting file handle process detection..."

        # ensure handle.exe from sysinternals is available before proceeding
        GenXdev.Windows\EnsurePSTools -PSExeName 'handle.exe'

        # log the path to handle.exe to help with troubleshooting
        Microsoft.PowerShell.Utility\Write-Verbose "Using handle.exe at: $HandleExePath"
    }

    process {

        # process each file path provided by the user
        foreach ($file in $FilePath) {

            # log which file we are currently checking
            Microsoft.PowerShell.Utility\Write-Verbose "Checking file handles for: $file"

            try {
                # execute handle.exe to get file handle information
                # -accepteula: automatically accept the eula
                # -a: show all information about file handles
                # -u: show paths in unicode format
                $handleOutput = & handle.exe -accepteula -a -u $file 2>$null

                # check if handle.exe executed successfully
                if ($LASTEXITCODE -ne 0) {
                    Microsoft.PowerShell.Utility\Write-Warning (
                        "Handle.exe returned exit code $LASTEXITCODE " +
                        "for file: $file"
                    )
                    continue
                }

                # parse output to find processes with file handles
                # first filter for lines containing "pid:" which indicate a process handle
                $processes = $handleOutput |
                Microsoft.PowerShell.Core\Where-Object {
                    $_ -match "pid:"
                } |
                Microsoft.PowerShell.Core\ForEach-Object {
                    # match the pattern for pid and ensure it's the correct file
                    if ($_ -match "pid:\s*(\d+)\s+type:\s*File\s+.*$([regex]::Escape($file))") {
                        # extract the process id from the regex match
                        $processId = $Matches[1]
                        Microsoft.PowerShell.Utility\Write-Verbose (
                            "Found process with PID $processId accessing file: $file"
                        )

                        try {
                            # get detailed information about the process
                            $process = Microsoft.PowerShell.Management\Get-Process -Id $processId -ErrorAction Stop

                            # create and return a custom object with process details
                            [PSCustomObject]@{
                                ProcessName = $process.ProcessName
                                PID         = [int]$processId
                                FilePath    = $file
                                ProcessPath = $process.Path
                            }
                        }
                        catch {
                            # handle case where process info can't be retrieved
                            Microsoft.PowerShell.Utility\Write-Warning (
                                "Could not retrieve process details for PID $processId"
                            )

                            # return object with available information
                            [PSCustomObject]@{
                                ProcessName = "Unknown"
                                PID         = [int]$processId
                                FilePath    = $file
                                ProcessPath = $null
                            }
                        }
                    }
                }

                # return the results or log that none were found
                if ($processes) {
                    Microsoft.PowerShell.Utility\Write-Verbose (
                        "Found $($processes.Count) process(es) with handles to: $file"
                    )
                    $processes
                }
                else {
                    Microsoft.PowerShell.Utility\Write-Verbose "No processes found with handles to: $file"
                }
            }
            catch {
                # handle any errors that occur during processing
                Microsoft.PowerShell.Utility\Write-Error (
                    "Error checking file handles for '$file': $($_.Exception.Message)"
                )
            }
        }
    }

    end {
        # log completion of the function
        Microsoft.PowerShell.Utility\Write-Verbose "Completed file handle process detection"
    }
}
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