c# - simbolico - mklink/d

¿Cómo crear un enlace duro en C#?

Question

¿Cómo crear un enlace duro en C #? Cualquier fragmento de código, por favor?

Answer 1

Echa un vistazo a este proyecto: clase Hardlink

Answer 2

El BCL no proporciona esto, por lo que tendrá que recurrir a p / invoke

[DllImport("Kernel32.dll", CharSet = CharSet.Unicode )]
  static extern bool CreateHardLink(
      string lpFileName,
      string lpExistingFileName,
      IntPtr lpSecurityAttributes
  );

Y usarlo, por ejemplo, como

 CreateHardLink(@"c:/temp/New Link", @"c:/temp/Original File",IntPtr.Zero);

Answer 3

Si solo desea crear un enlace físico a un archivo, la respuesta

using System.Runtime.InteropServices;
...
[DllImport("Kernel32.dll", CharSet = CharSet.Unicode )]
  static extern bool CreateHardLink(
      string lpFileName,
      string lpExistingFileName,
      IntPtr lpSecurityAttributes
  );

parece ser el mejor

Pero si desea crear un enlace físico de una carpeta, entonces es un poco más complicado.
Here encontré algo de código para crear / eliminar enlaces de carpeta (uniones). Probé el código y funcionó correctamente.
Publico el código aquí, en caso de que el sitio se desconecte:

JunctionPoint.cs

// File: RollThroughLibrary/CreateMaps/JunctionPoint.cs
// User: Adrian Hum/
// 
// Created:  2017-11-19 2:46 PM
// Modified: 2017-11-19 6:10 PM

using System;
using System.Diagnostics.CodeAnalysis;
using System.IO;
using System.Runtime.InteropServices;
using System.Text;
using Microsoft.Win32.SafeHandles;

namespace CreateMaps
{
    /// <summary>
    ///     Provides access to NTFS junction points in .Net.
    /// </summary>
    [SuppressMessage("ReSharper", "InconsistentNaming")]
    [SuppressMessage("ReSharper", "UnusedMember.Local")]
    [SuppressMessage("ReSharper", "MemberCanBePrivate.Local")]
    [SuppressMessage("ReSharper", "FieldCanBeMadeReadOnly.Local")]
    public static class JunctionPoint
    {
        /// <summary>
        ///     The file or directory is not a reparse point.
        /// </summary>
        private const int ERROR_NOT_A_REPARSE_POINT = 4390;

        /// <summary>
        ///     The reparse point attribute cannot be set because it conflicts with an existing attribute.
        /// </summary>
        private const int ERROR_REPARSE_ATTRIBUTE_CONFLICT = 4391;

        /// <summary>
        ///     The data present in the reparse point buffer is invalid.
        /// </summary>
        private const int ERROR_INVALID_REPARSE_DATA = 4392;

        /// <summary>
        ///     The tag present in the reparse point buffer is invalid.
        /// </summary>
        private const int ERROR_REPARSE_TAG_INVALID = 4393;

        /// <summary>
        ///     There is a mismatch between the tag specified in the request and the tag present in the reparse point.
        /// </summary>
        private const int ERROR_REPARSE_TAG_MISMATCH = 4394;

        /// <summary>
        ///     Command to set the reparse point data block.
        /// </summary>
        private const int FSCTL_SET_REPARSE_POINT = 0x000900A4;

        /// <summary>
        ///     Command to get the reparse point data block.
        /// </summary>
        private const int FSCTL_GET_REPARSE_POINT = 0x000900A8;

        /// <summary>
        ///     Command to delete the reparse point data base.
        /// </summary>
        private const int FSCTL_DELETE_REPARSE_POINT = 0x000900AC;

        /// <summary>
        ///     Reparse point tag used to identify mount points and junction points.
        /// </summary>
        private const uint IO_REPARSE_TAG_MOUNT_POINT = 0xA0000003;

        /// <summary>
        ///     This prefix indicates to NTFS that the path is to be treated as a non-interpreted
        ///     path in the virtual file system.
        /// </summary>
        private const string NonInterpretedPathPrefix = @"/??/";

        [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern bool DeviceIoControl(IntPtr hDevice, uint dwIoControlCode,
            IntPtr InBuffer, int nInBufferSize,
            IntPtr OutBuffer, int nOutBufferSize,
            out int pBytesReturned, IntPtr lpOverlapped);

        [DllImport("kernel32.dll", SetLastError = true)]
        private static extern IntPtr CreateFile(
            string lpFileName,
            EFileAccess dwDesiredAccess,
            EFileShare dwShareMode,
            IntPtr lpSecurityAttributes,
            ECreationDisposition dwCreationDisposition,
            EFileAttributes dwFlagsAndAttributes,
            IntPtr hTemplateFile);

        /// <summary>
        ///     Creates a junction point from the specified directory to the specified target directory.
        /// </summary>
        /// <remarks>
        ///     Only works on NTFS.
        /// </remarks>
        /// <param name="junctionPoint">The junction point path</param>
        /// <param name="targetDir">The target directory</param>
        /// <param name="overwrite">If true overwrites an existing reparse point or empty directory</param>
        /// <exception cref="IOException">
        ///     Thrown when the junction point could not be created or when
        ///     an existing directory was found and <paramref name="overwrite" /> if false
        /// </exception>
        public static void Create(string junctionPoint, string targetDir, bool overwrite)
        {
            targetDir = Path.GetFullPath(targetDir);

            if (!Directory.Exists(targetDir))
                throw new IOException("Target path does not exist or is not a directory.");

            if (Directory.Exists(junctionPoint))
            {
                if (!overwrite)
                    throw new IOException("Directory already exists and overwrite parameter is false.");
            }
            else
            {
                Directory.CreateDirectory(junctionPoint);
            }

            using (var handle = OpenReparsePoint(junctionPoint, EFileAccess.GenericWrite))
            {
                var targetDirBytes = Encoding.Unicode.GetBytes(NonInterpretedPathPrefix + Path.GetFullPath(targetDir));

                var reparseDataBuffer =
                    new REPARSE_DATA_BUFFER
                    {
                        ReparseTag = IO_REPARSE_TAG_MOUNT_POINT,
                        ReparseDataLength = (ushort)(targetDirBytes.Length + 12),
                        SubstituteNameOffset = 0,
                        SubstituteNameLength = (ushort)targetDirBytes.Length,
                        PrintNameOffset = (ushort)(targetDirBytes.Length + 2),
                        PrintNameLength = 0,
                        PathBuffer = new byte[0x3ff0]
                    };

                Array.Copy(targetDirBytes, reparseDataBuffer.PathBuffer, targetDirBytes.Length);

                var inBufferSize = Marshal.SizeOf(reparseDataBuffer);
                var inBuffer = Marshal.AllocHGlobal(inBufferSize);

                try
                {
                    Marshal.StructureToPtr(reparseDataBuffer, inBuffer, false);

                    int bytesReturned;
                    var result = DeviceIoControl(handle.DangerousGetHandle(), FSCTL_SET_REPARSE_POINT,
                        inBuffer, targetDirBytes.Length + 20, IntPtr.Zero, 0, out bytesReturned, IntPtr.Zero);

                    if (!result)
                        ThrowLastWin32Error("Unable to create junction point.");
                }
                finally
                {
                    Marshal.FreeHGlobal(inBuffer);
                }
            }
        }

        /// <summary>
        ///     Deletes a junction point at the specified source directory along with the directory itself.
        ///     Does nothing if the junction point does not exist.
        /// </summary>
        /// <remarks>
        ///     Only works on NTFS.
        /// </remarks>
        /// <param name="junctionPoint">The junction point path</param>
        public static void Delete(string junctionPoint)
        {
            if (!Directory.Exists(junctionPoint))
            {
                if (File.Exists(junctionPoint))
                    throw new IOException("Path is not a junction point.");

                return;
            }

            using (var handle = OpenReparsePoint(junctionPoint, EFileAccess.GenericWrite))
            {
                var reparseDataBuffer = new REPARSE_DATA_BUFFER
                {
                    ReparseTag = IO_REPARSE_TAG_MOUNT_POINT,
                    ReparseDataLength = 0,
                    PathBuffer = new byte[0x3ff0]
                };


                var inBufferSize = Marshal.SizeOf(reparseDataBuffer);
                var inBuffer = Marshal.AllocHGlobal(inBufferSize);
                try
                {
                    Marshal.StructureToPtr(reparseDataBuffer, inBuffer, false);

                    int bytesReturned;
                    var result = DeviceIoControl(handle.DangerousGetHandle(), FSCTL_DELETE_REPARSE_POINT,
                        inBuffer, 8, IntPtr.Zero, 0, out bytesReturned, IntPtr.Zero);

                    if (!result)
                        ThrowLastWin32Error("Unable to delete junction point.");
                }
                finally
                {
                    Marshal.FreeHGlobal(inBuffer);
                }

                try
                {
                    Directory.Delete(junctionPoint);
                }
                catch (IOException ex)
                {
                    throw new IOException("Unable to delete junction point.", ex);
                }
            }
        }

        /// <summary>
        ///     Determines whether the specified path exists and refers to a junction point.
        /// </summary>
        /// <param name="path">The junction point path</param>
        /// <returns>True if the specified path represents a junction point</returns>
        /// <exception cref="IOException">
        ///     Thrown if the specified path is invalid
        ///     or some other error occurs
        /// </exception>
        public static bool Exists(string path)
        {
            if (!Directory.Exists(path))
                return false;

            using (var handle = OpenReparsePoint(path, EFileAccess.GenericRead))
            {
                var target = InternalGetTarget(handle);
                return target != null;
            }
        }

        /// <summary>
        ///     Gets the target of the specified junction point.
        /// </summary>
        /// <remarks>
        ///     Only works on NTFS.
        /// </remarks>
        /// <param name="junctionPoint">The junction point path</param>
        /// <returns>The target of the junction point</returns>
        /// <exception cref="IOException">
        ///     Thrown when the specified path does not
        ///     exist, is invalid, is not a junction point, or some other error occurs
        /// </exception>
        public static string GetTarget(string junctionPoint)
        {
            using (var handle = OpenReparsePoint(junctionPoint, EFileAccess.GenericRead))
            {
                var target = InternalGetTarget(handle);
                if (target == null)
                    throw new IOException("Path is not a junction point.");

                return target;
            }
        }

        private static string InternalGetTarget(SafeFileHandle handle)
        {
            var outBufferSize = Marshal.SizeOf(typeof(REPARSE_DATA_BUFFER));
            var outBuffer = Marshal.AllocHGlobal(outBufferSize);

            try
            {
                int bytesReturned;
                var result = DeviceIoControl(handle.DangerousGetHandle(), FSCTL_GET_REPARSE_POINT,
                    IntPtr.Zero, 0, outBuffer, outBufferSize, out bytesReturned, IntPtr.Zero);

                if (!result)
                {
                    var error = Marshal.GetLastWin32Error();
                    if (error == ERROR_NOT_A_REPARSE_POINT)
                        return null;

                    ThrowLastWin32Error("Unable to get information about junction point.");
                }

                var reparseDataBuffer = (REPARSE_DATA_BUFFER)
                    Marshal.PtrToStructure(outBuffer, typeof(REPARSE_DATA_BUFFER));

                if (reparseDataBuffer.ReparseTag != IO_REPARSE_TAG_MOUNT_POINT)
                    return null;

                var targetDir = Encoding.Unicode.GetString(reparseDataBuffer.PathBuffer,
                    reparseDataBuffer.SubstituteNameOffset, reparseDataBuffer.SubstituteNameLength);

                if (targetDir.StartsWith(NonInterpretedPathPrefix))
                    targetDir = targetDir.Substring(NonInterpretedPathPrefix.Length);

                return targetDir;
            }
            finally
            {
                Marshal.FreeHGlobal(outBuffer);
            }
        }

        private static SafeFileHandle OpenReparsePoint(string reparsePoint, EFileAccess accessMode)
        {
            var reparsePointHandle = new SafeFileHandle(CreateFile(reparsePoint, accessMode,
                EFileShare.Read | EFileShare.Write | EFileShare.Delete,
                IntPtr.Zero, ECreationDisposition.OpenExisting,
                EFileAttributes.BackupSemantics | EFileAttributes.OpenReparsePoint, IntPtr.Zero), true);

            if (Marshal.GetLastWin32Error() != 0)
                ThrowLastWin32Error("Unable to open reparse point.");

            return reparsePointHandle;
        }

        private static void ThrowLastWin32Error(string message)
        {
            throw new IOException(message, Marshal.GetExceptionForHR(Marshal.GetHRForLastWin32Error()));
        }

        [Flags]
        private enum EFileAccess : uint
        {
            GenericRead = 0x80000000,
            GenericWrite = 0x40000000,
            GenericExecute = 0x20000000,
            GenericAll = 0x10000000
        }

        [Flags]
        private enum EFileShare : uint
        {
            None = 0x00000000,
            Read = 0x00000001,
            Write = 0x00000002,
            Delete = 0x00000004
        }

        private enum ECreationDisposition : uint
        {
            New = 1,
            CreateAlways = 2,
            OpenExisting = 3,
            OpenAlways = 4,
            TruncateExisting = 5
        }

        [Flags]
        private enum EFileAttributes : uint
        {
            Readonly = 0x00000001,
            Hidden = 0x00000002,
            System = 0x00000004,
            Directory = 0x00000010,
            Archive = 0x00000020,
            Device = 0x00000040,
            Normal = 0x00000080,
            Temporary = 0x00000100,
            SparseFile = 0x00000200,
            ReparsePoint = 0x00000400,
            Compressed = 0x00000800,
            Offline = 0x00001000,
            NotContentIndexed = 0x00002000,
            Encrypted = 0x00004000,
            Write_Through = 0x80000000,
            Overlapped = 0x40000000,
            NoBuffering = 0x20000000,
            RandomAccess = 0x10000000,
            SequentialScan = 0x08000000,
            DeleteOnClose = 0x04000000,
            BackupSemantics = 0x02000000,
            PosixSemantics = 0x01000000,
            OpenReparsePoint = 0x00200000,
            OpenNoRecall = 0x00100000,
            FirstPipeInstance = 0x00080000
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct REPARSE_DATA_BUFFER
        {
            /// <summary>
            ///     Reparse point tag. Must be a Microsoft reparse point tag.
            /// </summary>
            public uint ReparseTag;

            /// <summary>
            ///     Size, in bytes, of the data after the Reserved member. This can be calculated by:
            ///     (4 * sizeof(ushort)) + SubstituteNameLength + PrintNameLength +
            ///     (namesAreNullTerminated ? 2 * sizeof(char) : 0);
            /// </summary>
            public ushort ReparseDataLength;

            /// <summary>
            ///     Reserved; do not use.
            /// </summary>
            public ushort Reserved;

            /// <summary>
            ///     Offset, in bytes, of the substitute name string in the PathBuffer array.
            /// </summary>
            public ushort SubstituteNameOffset;

            /// <summary>
            ///     Length, in bytes, of the substitute name string. If this string is null-terminated,
            ///     SubstituteNameLength does not include space for the null character.
            /// </summary>
            public ushort SubstituteNameLength;

            /// <summary>
            ///     Offset, in bytes, of the print name string in the PathBuffer array.
            /// </summary>
            public ushort PrintNameOffset;

            /// <summary>
            ///     Length, in bytes, of the print name string. If this string is null-terminated,
            ///     PrintNameLength does not include space for the null character.
            /// </summary>
            public ushort PrintNameLength;

            /// <summary>
            ///     A buffer containing the unicode-encoded path string. The path string contains
            ///     the substitute name string and print name string.
            /// </summary>
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 0x3FF0)]
            public byte[] PathBuffer;
        }
    }
}

Uso:

using CreateMaps;
...
JunctionPoint.Create(@"C:/Temp/HardlinkFolderToCreate", @"C:/Temp/ExistingFolder", false);

Answer 4

Si te refieres a los enlaces duros de NTFS:

Lo siguiente es ( una introducción de texto en dotnetspark ):

Desafortunadamente, ni los enlaces duros ni los enlaces blandos son compatibles con .NET Framework. Por lo tanto, deberá profundizar en la API de Windows para permitir que su aplicación consuma esta función. Puede crear un enlace fijo utilizando una sola línea de código mediante una simple llamada a la función Win32, CreateHardLink (), que reside en la biblioteca Kernel32.dll. La definición de esta función es la siguiente:

BOOL CreateHardLink(
  LPCTSTR lpFileName,
  LPCTSTR lpExistingFileName,
  LPSECURITY_ATTRIBUTES lpSecurityAttributes
);

Answer 5

[DllImport("Kernel32.dll", CharSet = CharSet.Unicode )]
  static extern bool CreateHardLink(
  string lpFileName,
  string lpExistingFileName,
  IntPtr lpSecurityAttributes
  );

Uso:

CreateHardLink(newLinkPath,sourcePath, IntPtr.Zero);

Answer 6

Process.Start("mklink /H", String.Format("{0} {1}", link, target));