subroutine opener (filename$)
    if exists(filename$) then
	print filename$; " exists"
    else
	print filename$; " does not exists"
    end if
end subroutine

call opener ("input.txt")
call opener ("\input.txt")
call opener ("docs\nul")
call opener ("\docs\nul")
call opener ("empty.kbs")
call opener ("`Abdu'l-Bahá.txt"))
end