Procedimiento para usar canalizaciones anónimas para la comunicación local entre procesos

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Las canalizaciones anónimas permiten la comunicación entre procesos en un equipo local. Proporcionan menos funcionalidad que las canalizaciones con nombre, pero también tienen menos carga de procesamiento. Puede utilizar las canalizaciones anónimas para facilitar la comunicación entre procesos en un equipo local. No se puede utilizar las canalizaciones anónimas para la comunicación a través de una red.

Para implementar canalizaciones anónimas, use las clases AnonymousPipeServerStream y AnonymousPipeClientStream.

Ejemplo 1

En el ejemplo siguiente se muestra una manera de enviar una cadena de un proceso primario a un proceso secundario mediante canalizaciones anónimas. En este ejemplo se crea un objeto AnonymousPipeServerStream en un proceso primario con un valor PipeDirection de Out. A continuación, el proceso primario crea un proceso secundario mediante un identificador de cliente para crear un objeto AnonymousPipeClientStream. El proceso secundario tiene un valor PipeDirection de In.

El proceso primario envía a continuación una cadena proporcionada por usuario al proceso secundario. La cadena se muestra a la consola en el proceso secundario.

En el ejemplo siguiente se muestra el proceso del servidor.

#using <System.dll>
#using <System.Core.dll>

using namespace System;
using namespace System::IO;
using namespace System::IO::Pipes;
using namespace System::Diagnostics;

ref class PipeServer
{
public:
    static void Main()
    {
        Process^ pipeClient = gcnew Process();

        pipeClient->StartInfo->FileName = "pipeClient.exe";

        AnonymousPipeServerStream^ pipeServer =
            gcnew AnonymousPipeServerStream(PipeDirection::Out,
            HandleInheritability::Inheritable);

        Console::WriteLine("[SERVER] Current TransmissionMode: {0}.",
            pipeServer->TransmissionMode);

        // Pass the client process a handle to the server.
        pipeClient->StartInfo->Arguments =
            pipeServer->GetClientHandleAsString();
        pipeClient->StartInfo->UseShellExecute = false;
        pipeClient->Start();

        pipeServer->DisposeLocalCopyOfClientHandle();

        try
        {
            // Read user input and send that to the client process.
            StreamWriter^ sw = gcnew StreamWriter(pipeServer);

            sw->AutoFlush = true;
            // Send a 'sync message' and wait for client to receive it.
            sw->WriteLine("SYNC");
            pipeServer->WaitForPipeDrain();
            // Send the console input to the client process.
            Console::Write("[SERVER] Enter text: ");
            sw->WriteLine(Console::ReadLine());
            sw->Close();
        }
        // Catch the IOException that is raised if the pipe is broken
        // or disconnected.
        catch (IOException^ e)
        {
            Console::WriteLine("[SERVER] Error: {0}", e->Message);
        }
        pipeServer->Close();
        pipeClient->WaitForExit();
        pipeClient->Close();
        Console::WriteLine("[SERVER] Client quit. Server terminating.");
    }
};

int main()
{
    PipeServer::Main();
}

using System;
using System.IO;
using System.IO.Pipes;
using System.Diagnostics;

class PipeServer
{
    static void Main()
    {
        Process pipeClient = new Process();

        pipeClient.StartInfo.FileName = "pipeClient.exe";

        using (AnonymousPipeServerStream pipeServer =
            new AnonymousPipeServerStream(PipeDirection.Out,
            HandleInheritability.Inheritable))
        {
            Console.WriteLine("[SERVER] Current TransmissionMode: {0}.",
                pipeServer.TransmissionMode);

            // Pass the client process a handle to the server.
            pipeClient.StartInfo.Arguments =
                pipeServer.GetClientHandleAsString();
            pipeClient.StartInfo.UseShellExecute = false;
            pipeClient.Start();

            pipeServer.DisposeLocalCopyOfClientHandle();

            try
            {
                // Read user input and send that to the client process.
                using (StreamWriter sw = new StreamWriter(pipeServer))
                {
                    sw.AutoFlush = true;
                    // Send a 'sync message' and wait for client to receive it.
                    sw.WriteLine("SYNC");
                    pipeServer.WaitForPipeDrain();
                    // Send the console input to the client process.
                    Console.Write("[SERVER] Enter text: ");
                    sw.WriteLine(Console.ReadLine());
                }
            }
            // Catch the IOException that is raised if the pipe is broken
            // or disconnected.
            catch (IOException e)
            {
                Console.WriteLine("[SERVER] Error: {0}", e.Message);
            }
        }

        pipeClient.WaitForExit();
        pipeClient.Close();
        Console.WriteLine("[SERVER] Client quit. Server terminating.");
    }
}

Imports System.IO
Imports System.IO.Pipes
Imports System.Diagnostics

Class PipeServer
    Shared Sub Main()
        Dim pipeClient As New Process()

        pipeClient.StartInfo.FileName = "pipeClient.exe"

        Using pipeServer As New AnonymousPipeServerStream(PipeDirection.Out, _
            HandleInheritability.Inheritable)

            Console.WriteLine("[SERVER] Current TransmissionMode: {0}.",
                pipeServer.TransmissionMode)

            ' Pass the client process a handle to the server.
            pipeClient.StartInfo.Arguments = pipeServer.GetClientHandleAsString()
            pipeClient.StartInfo.UseShellExecute = false
            pipeClient.Start()

            pipeServer.DisposeLocalCopyOfClientHandle()

            Try
                ' Read user input and send that to the client process.
                Using sw As New StreamWriter(pipeServer)
                    sw.AutoFlush = true
                    ' Send a 'sync message' and wait for client to receive it.
                    sw.WriteLine("SYNC")
                    pipeServer.WaitForPipeDrain()
                    ' Send the console input to the client process.
                    Console.Write("[SERVER] Enter text: ")
                    sw.WriteLine(Console.ReadLine())
                End Using
            Catch e As IOException
                ' Catch the IOException that is raised if the pipe is broken
                ' or disconnected.
                Console.WriteLine("[SERVER] Error: {0}", e.Message)
            End Try
        End Using

        pipeClient.WaitForExit()
        pipeClient.Close()
        Console.WriteLine("[SERVER] Client quit. Server terminating.")
    End Sub
End Class

Ejemplo 2

En el ejemplo siguiente se muestra el proceso del cliente. El proceso de servidor inicia el proceso de cliente y da un identificador de cliente a ese proceso. El ejecutable resultante del código de cliente debe denominarse pipeClient.exe y copiarse en el mismo directorio que el ejecutable del servidor antes de ejecutar el proceso de servidor.

#using <System.Core.dll>

using namespace System;
using namespace System::IO;
using namespace System::IO::Pipes;

ref class PipeClient
{
public:
    static void Main(array<String^>^ args)
    {
        if (args->Length > 1)
        {
            PipeStream^ pipeClient = gcnew AnonymousPipeClientStream(PipeDirection::In, args[1]);

            Console::WriteLine("[CLIENT] Current TransmissionMode: {0}.",
                pipeClient->TransmissionMode);

            StreamReader^ sr = gcnew StreamReader(pipeClient);

            // Display the read text to the console
            String^ temp;

            // Wait for 'sync message' from the server.
            do
            {
                Console::WriteLine("[CLIENT] Wait for sync...");
                temp = sr->ReadLine();
            }
            while (!temp->StartsWith("SYNC"));

            // Read the server data and echo to the console.
            while ((temp = sr->ReadLine()) != nullptr)
            {
                Console::WriteLine("[CLIENT] Echo: " + temp);
            }
            sr->Close();
            pipeClient->Close();
        }
        Console::Write("[CLIENT] Press Enter to continue...");
        Console::ReadLine();
    }
};

int main()
{
    array<String^>^ args = Environment::GetCommandLineArgs();
    PipeClient::Main(args);
}

using System;
using System.IO;
using System.IO.Pipes;

class PipeClient
{
    static void Main(string[] args)
    {
        if (args.Length > 0)
        {
            using (PipeStream pipeClient =
                new AnonymousPipeClientStream(PipeDirection.In, args[0]))
            {
                Console.WriteLine("[CLIENT] Current TransmissionMode: {0}.",
                   pipeClient.TransmissionMode);

                using (StreamReader sr = new StreamReader(pipeClient))
                {
                    // Display the read text to the console
                    string temp;

                    // Wait for 'sync message' from the server.
                    do
                    {
                        Console.WriteLine("[CLIENT] Wait for sync...");
                        temp = sr.ReadLine();
                    }
                    while (!temp.StartsWith("SYNC"));

                    // Read the server data and echo to the console.
                    while ((temp = sr.ReadLine()) != null)
                    {
                        Console.WriteLine("[CLIENT] Echo: " + temp);
                    }
                }
            }
        }
        Console.Write("[CLIENT] Press Enter to continue...");
        Console.ReadLine();
    }
}

Imports System.IO
Imports System.IO.Pipes

Class PipeClient
    Shared Sub Main(args() as String)
        If args.Length > 0 Then
            Using pipeClient As New AnonymousPipeClientStream(PipeDirection.In, args(0))
                Console.WriteLine("[CLIENT] Current TransmissionMode: {0}.", _
                   pipeClient.TransmissionMode)

                Using sr As New StreamReader(pipeClient)
                    ' Display the read text to the console
                    Dim temp As String

                    ' Wait for 'sync message' from the server.
                    Do
                        Console.WriteLine("[CLIENT] Wait for sync...")
                        temp = sr.ReadLine()
                    Loop While temp.StartsWith("SYNC") = False

                    ' Read the server data and echo to the console.
                    temp = sr.ReadLine()
                    While Not temp = Nothing
                        Console.WriteLine("[CLIENT] Echo: " + temp)
                        temp = sr.ReadLine()
                    End While
                End Using
            End Using
        End If
        Console.Write("[CLIENT] Press Enter to continue...")
        Console.ReadLine()
    End Sub
End Class

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