PHP 中的 TCP 客户端连接

我有一个连接到服务器的web服务，并以xml或json的形式返回结果。它是用 asp.net 写的。我想在 php 中使用相同的方法。

using (TcpClient tcpClient = new TcpClient()) 
    { 
        tcpClient.Connect("1.1.1.1", port: 42011);
        string search = "search^10|5|2|1^gagl^55592a782ce899d2" + 
System.Environment.NewLine; 
        using (NetworkStream ns = tcpClient.GetStream()) 
        { 
            byte[] bytes = ASCIIEncoding.ASCII.GetBytes(search); 
            ns.Write(bytes, 0, bytes.Length); 
            string result = ReadBuffer(ns); 
          // [.. consume result XML string ..] 
        } 
        tcpClient.Close(); 
    }
        }
protected string ReadBuffer(NetworkStream ns) 
{ 
    byte[] lenghtBuffer = new byte[4]; 
    int bytesRead = 0; 
    while (bytesRead < 4) 
        bytesRead += ns.Read(lenghtBuffer, bytesRead, 4 - bytesRead); 
    if (BitConverter.IsLittleEndian) 
        Array.Reverse(lenghtBuffer); 
    int responseLength = BitConverter.ToInt32(lenghtBuffer, 0); 
    byte[] buffer = new byte[responseLength]; 
    bytesRead = 0; 
    while (bytesRead < responseLength) 
        bytesRead += ns.Read(buffer, bytesRead, responseLength - bytesRead); 
    string result = ASCIIEncoding.ASCII.GetString(buffer, 0, bytesRead); 
    return result; 
} 

上面的代码返回 .net 中的值。如何使用相同的值在 php 中获取结果。