anchor.diff:                p = 1
             elseif (tag(1:2).eq.'-p') then
                 p = 1
  +          elseif (tag(1:2).eq.'-z') then
  +              z = 1
             elseif (tag(1:4).eq.'-min') then
                 i = i + 1
                 call getarg(i,tag)
  
positive.code:       write (*,*)
       1 '  -max [MXVAL] (Default undefined) maximum value in the list'
        write (*,*)
       1 '  -h/-?        Online help (this screen)'
        write (*,*) ''
        
  
negative.code: 
  C======================================================================C
  
        SUBROUTINE gcmdln(ifile,ofile,mnval,mxval,z,p,user)
  
        IMPLICIT none
        CHARACTER*30 tag
        CHARACTER*30 ifile,ofile
        INTEGER narg,i
        INTEGER mnval,mxval,user,p,z
  
        ifile = 'eventfrequency.in'
        ofile = 'eventfrequency.out'
  