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Date:Mon Apr 23 10:34:16 2003 
Subject:Re: Vector arguments to external procedures - correction 
From:davidy 
Volume-ID:1030423.02 

> Irrelevant reminiscence: many years ago, I changed the value of 2 this way.
> 
>...
> 
> Ah, those were the days ;-).

Were?? Well, I suppose there has been some progress - under present-day
Solaris, using Sun's Fortran compiler, this program:

      subroutine foo(x)
      x = x + 1
      return
      end

      call foo(2)
      end

produces a run-time error with the message "POSSIBLE ATTEMPT TO MODIFY
CONSTANT" followed by a segmentation fault!

And in "Structured Fortran 77 Programming with Hewlett-Packard
Computers" I read "Since a constant is meant to be a value not subject
to change, it should be used [as an actual argument] in those instances
where the subprogram's computations do not alter it."

Maybe you didn't read the manual.

David