anchor.diff:        zfile = 'none'
         cfile = 'none'
         nfile = 'none'
  +      efile = 'none'
  +      dfile = 'none'
         time = -1.0d0
         cf = 0
         narg = iargc()
  
positive.code: 
  C----------------------------------------------------------------------c
  
        SUBROUTINE gcmdln(ifile,sfile,tfile,zfile,cfile,nfile,time,cf)
        IMPLICIT none
        CHARACTER*40 tag,ifile,sfile,tfile,zfile,cfile,nfile
        INTEGER narg,i,cf
        REAL*8 time
        ifile = 'none'
  
negative.code:               cf = 1
                i = i + 1
                call getarg(i,cfile)
            elseif (tag(1:4).eq.'-epi') then
                i = i + 1
                call getarg(i,efile)
            elseif (tag(1:3).eq.'-dc') then
                i = i + 1
                call getarg(i,dfile)
            elseif (tag(1:7).eq.'-noslip') then
                i = i + 1
                call getarg(i,nfile)
  