using System;
using System.Collections;
using System.Threading;
using System.Data;
using Microsoft.SqlServer.Dts.Pipeline.Wrapper;
using Microsoft.SqlServer.Dts.Runtime.Wrapper;
using Microsoft.SqlServer.Dts.Pipeline;

[Microsoft.SqlServer.Dts.Pipeline.SSISScriptComponentEntryPointAttribute]
public class ScriptMain : UserComponent
{


    System.Collections.Generic.List<object> shared = null;
    System.Threading.ManualResetEvent sync;

    public override void ProcessInput(int InputID, PipelineBuffer Buffer)
    {
        lock (this)
        {
            if (InputID == 82)
            {
                if (shared == null)
                {
                    shared = new System.Collections.Generic.List<object>();
                    sync = new System.Threading.ManualResetEvent(false);
                    shared.Add(sync);
                    shared.Add(Buffer);
                    shared.Add(GetColumnIndexes(InputID));

                    IDTSVariables100 vars = null;

                    this.VariableDispenser.LockOneForWrite("Test", ref vars);

                    vars[0].Value = shared;
                    vars.Unlock();
                    sync.WaitOne();
                    System.Windows.Forms.MessageBox.Show("Done");
                }
            }
        }
    }
}

using System;
using System.Data;
using Microsoft.SqlServer.Dts.Pipeline;
using Microsoft.SqlServer.Dts.Pipeline.Wrapper;
using Microsoft.SqlServer.Dts.Runtime.Wrapper;

[Microsoft.SqlServer.Dts.Pipeline.SSISScriptComponentEntryPointAttribute]
public class ScriptMain : UserComponent
{
    System.Threading.ManualResetEvent sync = null;
    InputXBuffer sharedBuffer = null;

    public override void Input0_ProcessInput(Input0Buffer Buffer)
    {
        lock (this)                 // Only 1 thread at a time
        {
            if (sharedBuffer == null)
            {
                object Test = null;
                while (Test == null)
                {
                    System.Threading.Thread.Sleep(100);
                    IDTSVariables100 vars = null;
                    this.VariableDispenser.LockOneForRead("Test", ref vars);
                    Test = vars[0].Value;
                    vars.Unlock();
                }

                var sharedList = Test as System.Collections.Generic.List<object>;

                if (sharedList != null)
                {
                    sync = sharedList[0] as System.Threading.ManualResetEvent;
                    var buffer = sharedList[1] as PipelineBuffer;
                    var bufferColumnIndexes = sharedList[2] as int[];
                    sharedBuffer = new InputXBuffer(buffer, bufferColumnIndexes);
                }
            }
       }

        while (sharedBuffer.NextRow())
        {
            // ... do stuff with Script Component 1's shared input here...
        }
        sync.Set();     // Signal script 1 that we're done
    }
}