PipeTest/Parent/Parent.cs

using System;
using System.Diagnostics;

namespace PipeTest
{
    class Parent
    {
        private static bool Test(long size)
        {
            Console.WriteLine($"Testing: {size}");
            bool result = true;
            using (var p = new Process())
            {
                p.StartInfo.FileName = @".\Child.exe";
                p.StartInfo.Arguments = size.ToString();
                p.StartInfo.RedirectStandardOutput = true;
                if (! p.Start()) throw new Exception("子プロセス開始失敗");
                if (!p.WaitForExit(2000))
                {
                    result = false;
                    p.Kill();
                }
                //Console.Write(p.StandardOutput.ReadToEnd());
            }
            Console.WriteLine($"Result: {result}");
            return result;
        }
        static void Main(string[] args)
        {
            long size = 1;
            while (Test(size)) size *= 2;
            var max = size;
            var min = size / 2;
            while (min + 1 < max)
            {
                size = (min + max) / 2;
                if (Test(size))
                {
                    min = size;
                } else
                {
                    max = size;
                }
            }
            Console.WriteLine($"size of buffer: {min}");
        }
    }
}