Using C#, how does one figure out what process locked a file?
In Windows, how do I determine (using C#) what process locked a file?
Third-party tools are helpful, but not what I\'m looking for.
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The following was produced based on Iain Ballard's code dump. It is broken: it will occasionally lock up when you retrieve the handle name. This code doesn't contain any work-arounds for that issue, and .NET leaves few options:
Thread.Abortcan no longer abort a thread that's currently in a native method.So, with that disclaimer, here is the code to retrieve handles which has been adapted to work (apart from the occasional lock-up) both in 32 and 64 bit modes:
using System; using System.Collections.Generic; using System.Linq; using System.Runtime.ConstrainedExecution; using System.Runtime.InteropServices; namespace BrokenHandleRetrieval { class Program { static void Main(string[] args) { Console.WriteLine("Enumerates open handles."); Console.WriteLine("This *will* lock up on calling HandleInfo.Name from time to time. Thread.Abort() won't help."); foreach (var hi in HandleUtil.GetHandles().Where(hi => hi.Type == HandleType.File)) Console.WriteLine("pid: " + hi.ProcessId + ", name: " + hi.Name); } } public enum HandleType { Unknown, Other, File, Directory, SymbolicLink, Key, Process, Thread, Job, Session, WindowStation, Timer, Desktop, Semaphore, Token, Mutant, Section, Event, KeyedEvent, IoCompletion, IoCompletionReserve, TpWorkerFactory, AlpcPort, WmiGuid, UserApcReserve, } public class HandleInfo { public int ProcessId { get; private set; } public ushort Handle { get; private set; } public int GrantedAccess { get; private set; } public byte RawType { get; private set; } public HandleInfo(int processId, ushort handle, int grantedAccess, byte rawType) { ProcessId = processId; Handle = handle; GrantedAccess = grantedAccess; RawType = rawType; } private static Dictionary<byte, string> _rawTypeMap = new Dictionary<byte, string>(); private string _name, _typeStr; private HandleType _type; public string Name { get { if (_name == null) initTypeAndName(); return _name; } } public string TypeString { get { if (_typeStr == null) initType(); return _typeStr; } } public HandleType Type { get { if (_typeStr == null) initType(); return _type; } } private void initType() { if (_rawTypeMap.ContainsKey(RawType)) { _typeStr = _rawTypeMap[RawType]; _type = HandleTypeFromString(_typeStr); } else initTypeAndName(); } bool _typeAndNameAttempted = false; private void initTypeAndName() { if (_typeAndNameAttempted) return; _typeAndNameAttempted = true; IntPtr sourceProcessHandle = IntPtr.Zero; IntPtr handleDuplicate = IntPtr.Zero; try { sourceProcessHandle = NativeMethods.OpenProcess(0x40 /* dup_handle */, true, ProcessId); // To read info about a handle owned by another process we must duplicate it into ours // For simplicity, current process handles will also get duplicated; remember that process handles cannot be compared for equality if (!NativeMethods.DuplicateHandle(sourceProcessHandle, (IntPtr) Handle, NativeMethods.GetCurrentProcess(), out handleDuplicate, 0, false, 2 /* same_access */)) return; // Query the object type if (_rawTypeMap.ContainsKey(RawType)) _typeStr = _rawTypeMap[RawType]; else { int length; NativeMethods.NtQueryObject(handleDuplicate, OBJECT_INFORMATION_CLASS.ObjectTypeInformation, IntPtr.Zero, 0, out length); IntPtr ptr = IntPtr.Zero; try { ptr = Marshal.AllocHGlobal(length); if (NativeMethods.NtQueryObject(handleDuplicate, OBJECT_INFORMATION_CLASS.ObjectTypeInformation, ptr, length, out length) != NT_STATUS.STATUS_SUCCESS) return; _typeStr = Marshal.PtrToStringUni((IntPtr) ((int) ptr + 0x58 + 2 * IntPtr.Size)); _rawTypeMap[RawType] = _typeStr; } finally { Marshal.FreeHGlobal(ptr); } } _type = HandleTypeFromString(_typeStr); // Query the object name if (_typeStr != null && GrantedAccess != 0x0012019f && GrantedAccess != 0x00120189 && GrantedAccess != 0x120089) // don't query some objects that could get stuck { int length; NativeMethods.NtQueryObject(handleDuplicate, OBJECT_INFORMATION_CLASS.ObjectNameInformation, IntPtr.Zero, 0, out length); IntPtr ptr = IntPtr.Zero; try { ptr = Marshal.AllocHGlobal(length); if (NativeMethods.NtQueryObject(handleDuplicate, OBJECT_INFORMATION_CLASS.ObjectNameInformation, ptr, length, out length) != NT_STATUS.STATUS_SUCCESS) return; _name = Marshal.PtrToStringUni((IntPtr) ((int) ptr + 2 * IntPtr.Size)); } finally { Marshal.FreeHGlobal(ptr); } } } finally { NativeMethods.CloseHandle(sourceProcessHandle); if (handleDuplicate != IntPtr.Zero) NativeMethods.CloseHandle(handleDuplicate); } } public static HandleType HandleTypeFromString(string typeStr) { switch (typeStr) { case null: return HandleType.Unknown; case "File": return HandleType.File; case "IoCompletion": return HandleType.IoCompletion; case "TpWorkerFactory": return HandleType.TpWorkerFactory; case "ALPC Port": return HandleType.AlpcPort; case "Event": return HandleType.Event; case "Section": return HandleType.Section; case "Directory": return HandleType.Directory; case "KeyedEvent": return HandleType.KeyedEvent; case "Process": return HandleType.Process; case "Key": return HandleType.Key; case "SymbolicLink": return HandleType.SymbolicLink; case "Thread": return HandleType.Thread; case "Mutant": return HandleType.Mutant; case "WindowStation": return HandleType.WindowStation; case "Timer": return HandleType.Timer; case "Semaphore": return HandleType.Semaphore; case "Desktop": return HandleType.Desktop; case "Token": return HandleType.Token; case "Job": return HandleType.Job; case "Session": return HandleType.Session; case "IoCompletionReserve": return HandleType.IoCompletionReserve; case "WmiGuid": return HandleType.WmiGuid; case "UserApcReserve": return HandleType.UserApcReserve; default: return HandleType.Other; } } } public static class HandleUtil { public static IEnumerable<HandleInfo> GetHandles() { // Attempt to retrieve the handle information int length = 0x10000; IntPtr ptr = IntPtr.Zero; try { while (true) { ptr = Marshal.AllocHGlobal(length); int wantedLength; var result = NativeMethods.NtQuerySystemInformation(SYSTEM_INFORMATION_CLASS.SystemHandleInformation, ptr, length, out wantedLength); if (result == NT_STATUS.STATUS_INFO_LENGTH_MISMATCH) { length = Math.Max(length, wantedLength); Marshal.FreeHGlobal(ptr); ptr = IntPtr.Zero; } else if (result == NT_STATUS.STATUS_SUCCESS) break; else throw new Exception("Failed to retrieve system handle information."); } int handleCount = IntPtr.Size == 4 ? Marshal.ReadInt32(ptr) : (int) Marshal.ReadInt64(ptr); int offset = IntPtr.Size; int size = Marshal.SizeOf(typeof(SystemHandleEntry)); for (int i = 0; i < handleCount; i++) { var struc = (SystemHandleEntry) Marshal.PtrToStructure((IntPtr) ((int) ptr + offset), typeof(SystemHandleEntry)); yield return new HandleInfo(struc.OwnerProcessId, struc.Handle, struc.GrantedAccess, struc.ObjectTypeNumber); offset += size; } } finally { if (ptr != IntPtr.Zero) Marshal.FreeHGlobal(ptr); } } [StructLayout(LayoutKind.Sequential)] private struct SystemHandleEntry { public int OwnerProcessId; public byte ObjectTypeNumber; public byte Flags; public ushort Handle; public IntPtr Object; public int GrantedAccess; } } enum NT_STATUS { STATUS_SUCCESS = 0x00000000, STATUS_BUFFER_OVERFLOW = unchecked((int) 0x80000005L), STATUS_INFO_LENGTH_MISMATCH = unchecked((int) 0xC0000004L) } enum SYSTEM_INFORMATION_CLASS { SystemBasicInformation = 0, SystemPerformanceInformation = 2, SystemTimeOfDayInformation = 3, SystemProcessInformation = 5, SystemProcessorPerformanceInformation = 8, SystemHandleInformation = 16, SystemInterruptInformation = 23, SystemExceptionInformation = 33, SystemRegistryQuotaInformation = 37, SystemLookasideInformation = 45 } enum OBJECT_INFORMATION_CLASS { ObjectBasicInformation = 0, ObjectNameInformation = 1, ObjectTypeInformation = 2, ObjectAllTypesInformation = 3, ObjectHandleInformation = 4 } static class NativeMethods { [DllImport("ntdll.dll")] internal static extern NT_STATUS NtQuerySystemInformation( [In] SYSTEM_INFORMATION_CLASS SystemInformationClass, [In] IntPtr SystemInformation, [In] int SystemInformationLength, [Out] out int ReturnLength); [DllImport("ntdll.dll")] internal static extern NT_STATUS NtQueryObject( [In] IntPtr Handle, [In] OBJECT_INFORMATION_CLASS ObjectInformationClass, [In] IntPtr ObjectInformation, [In] int ObjectInformationLength, [Out] out int ReturnLength); [DllImport("kernel32.dll")] internal static extern IntPtr GetCurrentProcess(); [DllImport("kernel32.dll", SetLastError = true)] public static extern IntPtr OpenProcess( [In] int dwDesiredAccess, [In, MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, [In] int dwProcessId); [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)] [DllImport("kernel32.dll", SetLastError = true)] [return: MarshalAs(UnmanagedType.Bool)] internal static extern bool CloseHandle( [In] IntPtr hObject); [DllImport("kernel32.dll", SetLastError = true)] [return: MarshalAs(UnmanagedType.Bool)] public static extern bool DuplicateHandle( [In] IntPtr hSourceProcessHandle, [In] IntPtr hSourceHandle, [In] IntPtr hTargetProcessHandle, [Out] out IntPtr lpTargetHandle, [In] int dwDesiredAccess, [In, MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, [In] int dwOptions); } }讨论(0) -
The code I found here, https://vmccontroller.svn.codeplex.com/svn/VmcController/VmcServices/DetectOpenFiles.cs
Works for me much better than the code provided by Iain. Iain's code seemed to be acquiring a lock of its own. Here is my slightly modified version of the code above modified to return the string path of the files locked instead of the FileSystemInfo object,
using System; using System.Collections.Generic; //using System.EnterpriseServices; using System.IO; using System.Runtime.CompilerServices; using System.Runtime.ConstrainedExecution; using System.Runtime.InteropServices; using System.Security.Permissions; using System.Text; using System.Threading; using Microsoft.Win32.SafeHandles; namespace Crmc.Core.BuildTasks { using System.Diagnostics; using System.Linq; #region ENUMs internal enum NT_STATUS { STATUS_SUCCESS = 0x00000000, STATUS_BUFFER_OVERFLOW = unchecked((int)0x80000005L), STATUS_INFO_LENGTH_MISMATCH = unchecked((int)0xC0000004L) } internal enum SYSTEM_INFORMATION_CLASS { SystemBasicInformation = 0, SystemPerformanceInformation = 2, SystemTimeOfDayInformation = 3, SystemProcessInformation = 5, SystemProcessorPerformanceInformation = 8, SystemHandleInformation = 16, SystemInterruptInformation = 23, SystemExceptionInformation = 33, SystemRegistryQuotaInformation = 37, SystemLookasideInformation = 45 } internal enum OBJECT_INFORMATION_CLASS { ObjectBasicInformation = 0, ObjectNameInformation = 1, ObjectTypeInformation = 2, ObjectAllTypesInformation = 3, ObjectHandleInformation = 4 } [Flags] internal enum ProcessAccessRights { PROCESS_DUP_HANDLE = 0x00000040 } [Flags] internal enum DuplicateHandleOptions { DUPLICATE_CLOSE_SOURCE = 0x1, DUPLICATE_SAME_ACCESS = 0x2 } #endregion [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode = true)] internal sealed class SafeObjectHandle : SafeHandleZeroOrMinusOneIsInvalid { private SafeObjectHandle() : base(true) { } internal SafeObjectHandle(IntPtr preexistingHandle, bool ownsHandle) : base(ownsHandle) { base.SetHandle(preexistingHandle); } protected override bool ReleaseHandle() { return NativeMethods.CloseHandle(base.handle); } } [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode = true)] internal sealed class SafeProcessHandle : SafeHandleZeroOrMinusOneIsInvalid { private SafeProcessHandle() : base(true) { } internal SafeProcessHandle(IntPtr preexistingHandle, bool ownsHandle) : base(ownsHandle) { base.SetHandle(preexistingHandle); } protected override bool ReleaseHandle() { return NativeMethods.CloseHandle(base.handle); } } #region Native Methods internal static class NativeMethods { [DllImport("ntdll.dll")] internal static extern NT_STATUS NtQuerySystemInformation( [In] SYSTEM_INFORMATION_CLASS SystemInformationClass, [In] IntPtr SystemInformation, [In] int SystemInformationLength, [Out] out int ReturnLength); [DllImport("ntdll.dll")] internal static extern NT_STATUS NtQueryObject( [In] IntPtr Handle, [In] OBJECT_INFORMATION_CLASS ObjectInformationClass, [In] IntPtr ObjectInformation, [In] int ObjectInformationLength, [Out] out int ReturnLength); [DllImport("kernel32.dll", SetLastError = true)] internal static extern SafeProcessHandle OpenProcess( [In] ProcessAccessRights dwDesiredAccess, [In, MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, [In] int dwProcessId); [DllImport("kernel32.dll", SetLastError = true)] [return: MarshalAs(UnmanagedType.Bool)] internal static extern bool DuplicateHandle( [In] IntPtr hSourceProcessHandle, [In] IntPtr hSourceHandle, [In] IntPtr hTargetProcessHandle, [Out] out SafeObjectHandle lpTargetHandle, [In] int dwDesiredAccess, [In, MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, [In] DuplicateHandleOptions dwOptions); [DllImport("kernel32.dll")] internal static extern IntPtr GetCurrentProcess(); [DllImport("kernel32.dll", SetLastError = true)] internal static extern int GetProcessId( [In] IntPtr Process); [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)] [DllImport("kernel32.dll", SetLastError = true)] [return: MarshalAs(UnmanagedType.Bool)] internal static extern bool CloseHandle( [In] IntPtr hObject); [DllImport("kernel32.dll", SetLastError = true)] internal static extern int QueryDosDevice( [In] string lpDeviceName, [Out] StringBuilder lpTargetPath, [In] int ucchMax); } #endregion //[ComVisible(true), EventTrackingEnabled(true)] public class DetectOpenFiles// : ServicedComponent { private static Dictionary<string, string> deviceMap; private const string networkDevicePrefix = "\\Device\\LanmanRedirector\\"; private const int MAX_PATH = 260; private enum SystemHandleType { OB_TYPE_UNKNOWN = 0, OB_TYPE_TYPE = 1, OB_TYPE_DIRECTORY, OB_TYPE_SYMBOLIC_LINK, OB_TYPE_TOKEN, OB_TYPE_PROCESS, OB_TYPE_THREAD, OB_TYPE_UNKNOWN_7, OB_TYPE_EVENT, OB_TYPE_EVENT_PAIR, OB_TYPE_MUTANT, OB_TYPE_UNKNOWN_11, OB_TYPE_SEMAPHORE, OB_TYPE_TIMER, OB_TYPE_PROFILE, OB_TYPE_WINDOW_STATION, OB_TYPE_DESKTOP, OB_TYPE_SECTION, OB_TYPE_KEY, OB_TYPE_PORT, OB_TYPE_WAITABLE_PORT, OB_TYPE_UNKNOWN_21, OB_TYPE_UNKNOWN_22, OB_TYPE_UNKNOWN_23, OB_TYPE_UNKNOWN_24, //OB_TYPE_CONTROLLER, //OB_TYPE_DEVICE, //OB_TYPE_DRIVER, OB_TYPE_IO_COMPLETION, OB_TYPE_FILE }; private const int handleTypeTokenCount = 27; private static readonly string[] handleTypeTokens = new string[] { "", "", "Directory", "SymbolicLink", "Token", "Process", "Thread", "Unknown7", "Event", "EventPair", "Mutant", "Unknown11", "Semaphore", "Timer", "Profile", "WindowStation", "Desktop", "Section", "Key", "Port", "WaitablePort", "Unknown21", "Unknown22", "Unknown23", "Unknown24", "IoCompletion", "File" }; [StructLayout(LayoutKind.Sequential)] private struct SYSTEM_HANDLE_ENTRY { public int OwnerPid; public byte ObjectType; public byte HandleFlags; public short HandleValue; public int ObjectPointer; public int AccessMask; } /// <summary> /// Gets the open files enumerator. /// </summary> /// <param name="processId">The process id.</param> /// <returns></returns> public static IEnumerable<String> GetOpenFilesEnumerator(int processId) { return new OpenFiles(processId); } public static List<Process> GetProcessesUsingFile(string fName) { List<Process> result = new List<Process>(); foreach (var p in Process.GetProcesses()) { try { if (DetectOpenFiles.GetOpenFilesEnumerator(p.Id).Contains(fName)) { result.Add(p); } } catch { }//some processes will fail } return result; } private sealed class OpenFiles : IEnumerable<String> { private readonly int processId; internal OpenFiles(int processId) { this.processId = processId; } #region IEnumerable<FileSystemInfo> Members public IEnumerator<String> GetEnumerator() { NT_STATUS ret; int length = 0x10000; // Loop, probing for required memory. do { IntPtr ptr = IntPtr.Zero; RuntimeHelpers.PrepareConstrainedRegions(); try { RuntimeHelpers.PrepareConstrainedRegions(); try { } finally { // CER guarantees that the address of the allocated // memory is actually assigned to ptr if an // asynchronous exception occurs. ptr = Marshal.AllocHGlobal(length); } int returnLength; ret = NativeMethods.NtQuerySystemInformation(SYSTEM_INFORMATION_CLASS.SystemHandleInformation, ptr, length, out returnLength); if (ret == NT_STATUS.STATUS_INFO_LENGTH_MISMATCH) { // Round required memory up to the nearest 64KB boundary. length = ((returnLength + 0xffff) & ~0xffff); } else if (ret == NT_STATUS.STATUS_SUCCESS) { int handleCount = Marshal.ReadInt32(ptr); int offset = sizeof(int); int size = Marshal.SizeOf(typeof(SYSTEM_HANDLE_ENTRY)); for (int i = 0; i < handleCount; i++) { SYSTEM_HANDLE_ENTRY handleEntry = (SYSTEM_HANDLE_ENTRY)Marshal.PtrToStructure((IntPtr)((int)ptr + offset), typeof(SYSTEM_HANDLE_ENTRY)); if (handleEntry.OwnerPid == processId) { IntPtr handle = (IntPtr)handleEntry.HandleValue; SystemHandleType handleType; if (GetHandleType(handle, handleEntry.OwnerPid, out handleType) && handleType == SystemHandleType.OB_TYPE_FILE) { string devicePath; if (GetFileNameFromHandle(handle, handleEntry.OwnerPid, out devicePath)) { string dosPath; if (ConvertDevicePathToDosPath(devicePath, out dosPath)) { if (File.Exists(dosPath)) { yield return dosPath; // return new FileInfo(dosPath); } else if (Directory.Exists(dosPath)) { yield return dosPath; // new DirectoryInfo(dosPath); } } } } } offset += size; } } } finally { // CER guarantees that the allocated memory is freed, // if an asynchronous exception occurs. Marshal.FreeHGlobal(ptr); //sw.Flush(); //sw.Close(); } } while (ret == NT_STATUS.STATUS_INFO_LENGTH_MISMATCH); } #endregion #region IEnumerable Members System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() { return GetEnumerator(); } #endregion } #region Private Members private static bool GetFileNameFromHandle(IntPtr handle, int processId, out string fileName) { IntPtr currentProcess = NativeMethods.GetCurrentProcess(); bool remote = (processId != NativeMethods.GetProcessId(currentProcess)); SafeProcessHandle processHandle = null; SafeObjectHandle objectHandle = null; try { if (remote) { processHandle = NativeMethods.OpenProcess(ProcessAccessRights.PROCESS_DUP_HANDLE, true, processId); if (NativeMethods.DuplicateHandle(processHandle.DangerousGetHandle(), handle, currentProcess, out objectHandle, 0, false, DuplicateHandleOptions.DUPLICATE_SAME_ACCESS)) { handle = objectHandle.DangerousGetHandle(); } } return GetFileNameFromHandle(handle, out fileName, 200); } finally { if (remote) { if (processHandle != null) { processHandle.Close(); } if (objectHandle != null) { objectHandle.Close(); } } } } private static bool GetFileNameFromHandle(IntPtr handle, out string fileName, int wait) { using (FileNameFromHandleState f = new FileNameFromHandleState(handle)) { ThreadPool.QueueUserWorkItem(new WaitCallback(GetFileNameFromHandle), f); if (f.WaitOne(wait)) { fileName = f.FileName; return f.RetValue; } else { fileName = string.Empty; return false; } } } private class FileNameFromHandleState : IDisposable { private ManualResetEvent _mr; private IntPtr _handle; private string _fileName; private bool _retValue; public IntPtr Handle { get { return _handle; } } public string FileName { get { return _fileName; } set { _fileName = value; } } public bool RetValue { get { return _retValue; } set { _retValue = value; } } public FileNameFromHandleState(IntPtr handle) { _mr = new ManualResetEvent(false); this._handle = handle; } public bool WaitOne(int wait) { return _mr.WaitOne(wait, false); } public void Set() { try { _mr.Set(); } catch{} } #region IDisposable Members public void Dispose() { if (_mr != null) _mr.Close(); } #endregion } private static void GetFileNameFromHandle(object state) { FileNameFromHandleState s = (FileNameFromHandleState)state; string fileName; s.RetValue = GetFileNameFromHandle(s.Handle, out fileName); s.FileName = fileName; s.Set(); } private static bool GetFileNameFromHandle(IntPtr handle, out string fileName) { IntPtr ptr = IntPtr.Zero; RuntimeHelpers.PrepareConstrainedRegions(); try { int length = 0x200; // 512 bytes RuntimeHelpers.PrepareConstrainedRegions(); try { } finally { // CER guarantees the assignment of the allocated // memory address to ptr, if an ansynchronous exception // occurs. ptr = Marshal.AllocHGlobal(length); } NT_STATUS ret = NativeMethods.NtQueryObject(handle, OBJECT_INFORMATION_CLASS.ObjectNameInformation, ptr, length, out length); if (ret == NT_STATUS.STATUS_BUFFER_OVERFLOW) { RuntimeHelpers.PrepareConstrainedRegions(); try { } finally { // CER guarantees that the previous allocation is freed, // and that the newly allocated memory address is // assigned to ptr if an asynchronous exception occurs. Marshal.FreeHGlobal(ptr); ptr = Marshal.AllocHGlobal(length); } ret = NativeMethods.NtQueryObject(handle, OBJECT_INFORMATION_CLASS.ObjectNameInformation, ptr, length, out length); } if (ret == NT_STATUS.STATUS_SUCCESS) { fileName = Marshal.PtrToStringUni((IntPtr)((int)ptr + 8), (length - 9) / 2); return fileName.Length != 0; } } finally { // CER guarantees that the allocated memory is freed, // if an asynchronous exception occurs. Marshal.FreeHGlobal(ptr); } fileName = string.Empty; return false; } private static bool GetHandleType(IntPtr handle, int processId, out SystemHandleType handleType) { string token = GetHandleTypeToken(handle, processId); return GetHandleTypeFromToken(token, out handleType); } private static bool GetHandleType(IntPtr handle, out SystemHandleType handleType) { string token = GetHandleTypeToken(handle); return GetHandleTypeFromToken(token, out handleType); } private static bool GetHandleTypeFromToken(string token, out SystemHandleType handleType) { for (int i = 1; i < handleTypeTokenCount; i++) { if (handleTypeTokens[i] == token) { handleType = (SystemHandleType)i; return true; } } handleType = SystemHandleType.OB_TYPE_UNKNOWN; return false; } private static string GetHandleTypeToken(IntPtr handle, int processId) { IntPtr currentProcess = NativeMethods.GetCurrentProcess(); bool remote = (processId != NativeMethods.GetProcessId(currentProcess)); SafeProcessHandle processHandle = null; SafeObjectHandle objectHandle = null; try { if (remote) { processHandle = NativeMethods.OpenProcess(ProcessAccessRights.PROCESS_DUP_HANDLE, true, processId); if (NativeMethods.DuplicateHandle(processHandle.DangerousGetHandle(), handle, currentProcess, out objectHandle, 0, false, DuplicateHandleOptions.DUPLICATE_SAME_ACCESS)) { handle = objectHandle.DangerousGetHandle(); } } return GetHandleTypeToken(handle); } finally { if (remote) { if (processHandle != null) { processHandle.Close(); } if (objectHandle != null) { objectHandle.Close(); } } } } private static string GetHandleTypeToken(IntPtr handle) { int length; NativeMethods.NtQueryObject(handle, OBJECT_INFORMATION_CLASS.ObjectTypeInformation, IntPtr.Zero, 0, out length); IntPtr ptr = IntPtr.Zero; RuntimeHelpers.PrepareConstrainedRegions(); try { RuntimeHelpers.PrepareConstrainedRegions(); try { } finally { ptr = Marshal.AllocHGlobal(length); } if (NativeMethods.NtQueryObject(handle, OBJECT_INFORMATION_CLASS.ObjectTypeInformation, ptr, length, out length) == NT_STATUS.STATUS_SUCCESS) { return Marshal.PtrToStringUni((IntPtr)((int)ptr + 0x60)); } } finally { Marshal.FreeHGlobal(ptr); } return string.Empty; } private static bool ConvertDevicePathToDosPath(string devicePath, out string dosPath) { EnsureDeviceMap(); int i = devicePath.Length; while (i > 0 && (i = devicePath.LastIndexOf('\\', i - 1)) != -1) { string drive; if (deviceMap.TryGetValue(devicePath.Substring(0, i), out drive)) { dosPath = string.Concat(drive, devicePath.Substring(i)); return dosPath.Length != 0; } } dosPath = string.Empty; return false; } private static void EnsureDeviceMap() { if (deviceMap == null) { Dictionary<string, string> localDeviceMap = BuildDeviceMap(); Interlocked.CompareExchange<Dictionary<string, string>>(ref deviceMap, localDeviceMap, null); } } private static Dictionary<string, string> BuildDeviceMap() { string[] logicalDrives = Environment.GetLogicalDrives(); Dictionary<string, string> localDeviceMap = new Dictionary<string, string>(logicalDrives.Length); StringBuilder lpTargetPath = new StringBuilder(MAX_PATH); foreach (string drive in logicalDrives) { string lpDeviceName = drive.Substring(0, 2); NativeMethods.QueryDosDevice(lpDeviceName, lpTargetPath, MAX_PATH); localDeviceMap.Add(NormalizeDeviceName(lpTargetPath.ToString()), lpDeviceName); } localDeviceMap.Add(networkDevicePrefix.Substring(0, networkDevicePrefix.Length - 1), "\\"); return localDeviceMap; } private static string NormalizeDeviceName(string deviceName) { if (string.Compare(deviceName, 0, networkDevicePrefix, 0, networkDevicePrefix.Length, StringComparison.InvariantCulture) == 0) { string shareName = deviceName.Substring(deviceName.IndexOf('\\', networkDevicePrefix.Length) + 1); return string.Concat(networkDevicePrefix, shareName); } return deviceName; } #endregion } }讨论(0) -
Not very straightforward, but on Windows Vista and above you can use the Restart Manager APIs to see who is using a file. Internet Explorer caches settings includes details on using this to detect which process has
iexplore.exeopen.Omitting a lot of detail:
// Start an RM session RmStartSession(&sessionHandle, 0, sessionKey); // Register the file you are checking RmRegisterResources(sessionHandle, 1, filePathArray, 0, NULL, 0, NULL); // Get all processes that have that file open. RmGetList(sessionHAndle, &nProcInfoNeeded, &nProcInfo, processes, &rebootReason); RmEndSession(sessionHandle);讨论(0)
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