************************* Makefile

ROOTCFLAGS    = $(shell root-config --cflags)
ROOTLIBS      = $(shell root-config --libs) -lNew
ROOTGLIBS     = $(shell root-config --glibs)

CXXFLAGS      = -O2 -fPIC -I$(ROOTSYS)/include -DCOMPILED_ROOT
CC = gcc
OPTIM=  -O2 -fexpensive-optimizations -funroll-loops
CXXFLAGS +=$(ROOTCFLAGS)
LIBS = $(LIBM) $(ROOTLIBS) $(ROOTGLIBS)
hprod:   hprod.o
	$(CC) $(CXXFLAGS) -o hprod hprod.o $(LIBS)

********************* producer code. hprod.C
#include <TROOT.h>
#include <TPad.h>
#include <TMapFile.h>
#include <TH1.h>
#include <TH2.h>
#include <TProfile.h>
#include <TSystem.h>
#include <TCanvas.h>
#include <iostream>
#include <TRandom.h>
#include <TApplication.h>

using namespace std;
int main()
{

  TApplication app("app",0,0);
  TMapFile::SetMapAddress(0x4125c000);
  TMapFile* mfile = TMapFile::Create("hsimple.map","RECREATE", 100000,
                            "Demo memory mapped file with histograms");
  
   TH1F* hpx    = new TH1F("hpx","This is the px distribution",100,-4,4);
   
   hpx->SetFillColor(48);

   mfile->Print();

   Float_t px, py, pz;
   int ii = 0;
   while (1) {
     gRandom->Rannor(px,py);
     hpx->Fill(px);
     if (!(ii % 10)) {
       mfile->Update();       // updates all objects in shared memory
       if (!ii) mfile->ls();  // print contents of mapped file after
     }                         // first update
     ii++;
     gSystem->Sleep(100);
   }
}


****************************** producer compilation went ok.

g++ -O2 -fPIC -I/work/hallc/gzero/jianglai/ROOT/root/include -DCOMPILED_ROOT -D_REENTRANT -I/work/hallc/gzero/jianglai/ROOT/root/include   -c -o hprod.o hprod.C

gcc -O2 -fPIC -I/work/hallc/gzero/jianglai/ROOT/root/include -DCOMPILED_ROOT -D_REENTRANT -I/work/hallc/gzero/jianglai/ROOT/root/include -o hprod hprod.o  -L/work/hallc/gzero/jianglai/ROOT/root/lib -lCore -lCint -lHist -lGraf -lGraf3d -lGpad -lTree -lRint -lPostscript -lMatrix -lPhysics -lpthread -lm -ldl -rdynamic -lNew -L/work/hallc/gzero/jianglai/ROOT/root/lib -lCore -lCint -lHist -lGraf -lGraf3d -lGpad -lTree -lRint -lPostscript -lMatrix -lPhysics -lGui -lpthread -lm -ldl -rdynamic

******************************* what I get from $ROOTSTS/lib
libASImage.so      libGpad.so         libMinuit.so      libThread.so
libAfterImage.a    libGraf.so         libMySQL.so       libTree.so
libCint.so         libGraf3d.so       libNew.so         libTreePlayer.so
libCore.so         libGui.so          libPhysics.so     libTreeViewer.so
libEG.so           libHbook.so        libPostscript.so  libVMC.so
libFumili.so       libHist.so         libProof.so       libX3d.so
libGX11.so         libHistPainter.so  libProofGui.so    libfreetype.a
libGX11TTF.so      libHtml.so         libRGL.so
libGeom.so         libKrb5Auth.so     libRLDAP.so
libGeomPainter.so  libMatrix.so       libRint.so

***************************** Error messages
Error in <TMapFile::TMapFile>: no memory mapped file capability available
Use rootn.exe or link application against "-lNew"
Memory mapped file:   hsimple.map
Title:                Demo memory mapped file with histograms
Option:               file closed

********** Error messages if I ran it in rootn.exe/cint  
Error in <TApplication::TApplication>: only one instance of TApplication allowed
Memory mapped file:   hsimple.map
Title:                Demo memory mapped file with histograms
Option:               CREATE
Mapped Memory region: 0x4125c000 - 0x41275000 (0.10 MB)
Current breakval:     0x41264000
Object               Class                Size      
hpx                  TH1F                 1024      

 *** Break *** segmentation violation
 Generating stack trace...
BFD: Dwarf Error: Invalid or unhandled FORM value: 14.
BFD: Dwarf Error: Invalid or unhandled FORM value: 14.