program tstiom
C
C      read in multiple events to the common block
C
#include "stdlun.inc"
      integer lok,ifl,i,ntries,istr
      integer lstr(4)
      character*11 filin(4),filrd
      logical lrdit(4)

      data lrdit/.true.,.true.,.true.,.true./
      data filin/'stdtsthx.io','stdtstjx.io','stdtstix.io',
     1           'stdtstpx.io'/
      save lrdit

C initialize HEP logical units
      lnhwrt=0
      lnhdcy=0
      lnhout=22
      lnhrdm(1)=23
      lnhrdm(2)=24
      lnhrdm(3)=25
      lnhrdm(4)=26
C...open output file
      open(unit=lnhout,file='stdtstiom.lpt',status='new')
      call mcfio_init()		! initialize MCFio once only
C...open input files
      do 110 i = 1,4
        filrd=filin(i)
        lnhrd=lnhrdm(i)
        call stdxropen(filrd,ntries,istr,lok)
        if(lok.ne.0) then
            lrdit(i)=.false.
            write(lnhout,1001) filrd
        else
            lstr(i) = istr
            write(lnhout,1002) filrd,istr
        endif
 110  continue
C...book histograms
      call tstbkiom
C...now read events
      do while (lrdit(1).or.lrdit(2).or.lrdit(3).or.lrdit(4))
        call stdzero
        do i=1,4
          if(lrdit(i))then
 200        call stdxrdm(ifl,lstr(i),lok)
            if(lok.ne.0)then
              call stdxend(lstr(i))
              lrdit(i)=.false.
            else
C... keep looping if this is not a HEPEVT record
              if(ifl.ne.1) go to 200
C... fill histograms
              call tstfliom
            endif
          endif
        enddo
      enddo
C...print histograms
      call houtpu(lnhout)
      call histdo
1001  format(' could not open file ',a12)
1002  format(' file ',a12,' is input stream ',i2)
      end

      subroutine tstfliom
C... fill histograms
#include "stdhep.inc"

      integer i

      call hfill(11,float(nevhep),0.,1.)
      call hfill(12,float(nhep),0.,1.)
      do 100 i=1,nhep
        call hfill(13,float(idhep(i)),0.,1.)
        call hfill(14,float(isthep(i)),0.,1.)
        call hfill(15,float(jmohep(1,i)),0.,1.)
        call hfill(16,float(jmohep(2,i)),0.,1.)
        call hfill(17,float(jdahep(1,i)),0.,1.)
        call hfill(18,float(jdahep(2,i)),0.,1.)
        call hfill(19,float(jmulti(i)),0.,1.)
        call hfill(21,sngl(phep(1,i)),0.,1.)
        call hfill(22,sngl(phep(2,i)),0.,1.)
        call hfill(23,sngl(phep(3,i)),0.,1.)
        call hfill(24,sngl(phep(4,i)),0.,1.)
        call hfill(25,sngl(phep(5,i)),0.,1.)
        call hfill(26,sngl(vhep(1,i)),0.,1.)
        call hfill(27,sngl(vhep(2,i)),0.,1.)
        call hfill(28,sngl(vhep(3,i)),0.,1.)
        call hfill(29,sngl(vhep(4,i)),0.,1.)
 100  continue
      return
      end

      subroutine tstbkiom
C--- book histograms
C
      implicit none
C---   The HBOOK common
      real hmemor
      common/pawc/hmemor(50000)

C---   Setup the HBOOK memory limit.
      call hlimit(50000)
C---   Book histograms.

      call hbook1(11,'nevhep',100,0.0,100.0,0.)
      call hbook1(12,'nhep',100,0.,1000.,0.)
      call hbook1(13,'idhep',100,0.,100.,0.)
      call hbook1(14,'isthep',100,0.,200.,0.)
      call hbook1(15,'jmohep(1,)',100,0.,1000.,0.)
      call hbook1(16,'jmohep(2,)',100,0.,1000.,0.)
      call hbook1(17,'jdahep(1,)',100,0.,1000.,0.)
      call hbook1(18,'jdahep(2,)',100,0.,1000.,0.)
      call hbook1(19,'jmulti',20,0.,10.,0.)
      call hbook1(21,'phep(1,)',100,-100.,100.,0.)
      call hbook1(22,'phep(2,)',100,-100.,100.,0.)
      call hbook1(23,'phep(3,)',100,-1000.,1000.,0.)
      call hbook1(24,'phep(4,)',100,-1000.,1000.,0.)
      call hbook1(25,'phep(5,)',50,-250.,250.,0.)
      call hbook1(26,'vhep(1,)',10,-1.,1.,0.)
      call hbook1(27,'vhep(2,)',10,-1.,1.,0.)
      call hbook1(28,'vhep(3,)',10,-1.,1.,0.)
      call hbook1(29,'vhep(4,)',10,0.,1.,0.)
      return
      end