c===========================================================
c     Test program for subroutine 'dvfrom'.
c
c     Program expects one argument which is the filename
c     to be passed to 'dvfrom'
c===========================================================
      program         tdvfrom

      implicit        none

c-----------------------------------------------------------
c     The integer function 'iargc' returns the number of
c     arguments supplied to the program.  It is 
c     automatically available to all Fortran programs on 
c     most Unix systems, as is 'getarg' (see below).
c-----------------------------------------------------------
      integer         iargc,      indlnb

      integer         maxn
      parameter     ( maxn = 100 000 )
      real*8          v(maxn)
      integer         n

      character*256   fname

c-----------------------------------------------------------
c     Unless exactly one argument is supplied, print usage
c     message and exit.
c-----------------------------------------------------------
      if( iargc() .ne. 1 ) then
         write(0,*) 'usage: tdvfrom <file name>'
         write(0,*) 
         write(0,*) '       Use ''tdvfrom -'' to read ',
     &              'from standard input'
         stop
      end if

c-----------------------------------------------------------
c     The subroutine 'getarg' (Unix) takes 2 arguments.
c     The first is an integer input argument specifying 
c     which argument is to be fetched, the second is 
c     a character output argument which, on return,
c     contains the fetched argument.
c
c     Get the filename.
c-----------------------------------------------------------
      call getarg(1,fname)
c-----------------------------------------------------------
c     Call the routine ...
c-----------------------------------------------------------
      call dvfrom(fname,v,n,maxn)
c-----------------------------------------------------------
c     ... and report how many numbers were read.
c-----------------------------------------------------------
      write(0,*) 'tdvfrom: ', n, ' read from '//
     &           fname(1:indlnb(fname))

      stop
      end