C----------------------------------------------------------------------
        subroutine ftread(iunit,nrec,length,pbuff,status)

C       lowest-level routine to read a disk file record into a physical buffer

C       iunit   i  Fortran unit number to read from
C       nrec    i  number of the file record to read
C       length  i  number of bytes to read
C       pbuff   i  number of the physical buffer to read into
C       status  i  output error status

        integer iunit,nrec,length,pbuff,status

C       COMMON BLOCK DEFINITIONS:--------------------------------------------
        integer nb,ne
        parameter (nb = 20)
        parameter (ne = 512)

        integer bufnum,chdu,hdutyp,maxhdu,hdstrt,hdend,nxthdr,dtstrt
        integer nxtfld
        logical wrmode
        common/ft0001/bufnum(199),chdu(nb),hdutyp(nb),maxhdu(nb),
     &  wrmode(nb),hdstrt(nb,ne),hdend(nb),nxthdr(nb),dtstrt(nb),nxtfld

        integer buflun,currnt,reclen,bytnum,maxrec
        common/ftlbuf/buflun(nb),currnt(nb),reclen(nb),
     &  bytnum(nb),maxrec(nb)

C       have to use separate character arrays because of compiler limitations
        character*2880 b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,b12,b13,b14,
     &  b15,b16,b17,b18,b19,b20
        common /ftbuff/b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,b12,b13,b14,
     &  b15,b16,b17,b18,b19,b20
C       END OF COMMON BLOCK DEFINITIONS-----------------------------------

        integer ibuff,ios

C       test if desired record exists before trying to read it
        ibuff=bufnum(iunit)
        if (nrec .gt. maxrec(ibuff)) then
C             record doesn't exist, so return EOF error
              status=107
              return
        end if

        go to (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,
     &  19,20)pbuff

C       if got here, then pbuff is out of range
        status=101
        return

1       read(iunit,rec=nrec,iostat=ios)b1(1:length)
        go to 100
2       read(iunit,rec=nrec,iostat=ios)b2(1:length)
        go to 100
3       read(iunit,rec=nrec,iostat=ios)b3(1:length)
        go to 100
4       read(iunit,rec=nrec,iostat=ios)b4(1:length)
        go to 100
5       read(iunit,rec=nrec,iostat=ios)b5(1:length)
        go to 100
6       read(iunit,rec=nrec,iostat=ios)b6(1:length)
        go to 100
7       read(iunit,rec=nrec,iostat=ios)b7(1:length)
        go to 100
8       read(iunit,rec=nrec,iostat=ios)b8(1:length)
        go to 100
9       read(iunit,rec=nrec,iostat=ios)b9(1:length)
        go to 100
10      read(iunit,rec=nrec,iostat=ios)b10(1:length)
        go to 100
11      read(iunit,rec=nrec,iostat=ios)b11(1:length)
        go to 100
12      read(iunit,rec=nrec,iostat=ios)b12(1:length)
        go to 100
13      read(iunit,rec=nrec,iostat=ios)b13(1:length)
        go to 100
14      read(iunit,rec=nrec,iostat=ios)b14(1:length)
        go to 100
15      read(iunit,rec=nrec,iostat=ios)b15(1:length)
        go to 100
16      read(iunit,rec=nrec,iostat=ios)b16(1:length)
        go to 100
17      read(iunit,rec=nrec,iostat=ios)b17(1:length)
        go to 100
18      read(iunit,rec=nrec,iostat=ios)b18(1:length)
        go to 100
19      read(iunit,rec=nrec,iostat=ios)b19(1:length)
        go to 100
20      read(iunit,rec=nrec,iostat=ios)b20(1:length)

100     continue
        if (ios .ne. 0)then
C               assume that this error indicates an end of file condition
                status=107
        end if
        end