Re: crash report
- From: Terence <tbwright@xxxxxxxxx>
- Date: Sat, 7 Mar 2009 20:59:45 -0800 (PST)
Terence <tbwright@xxxxxxxxx> wrote:Nick wrote:-
You cannot use unit 1 as a file on disk in most run-time compiled
In general, do not use units 0 through 3 and it is wiser to not use 4
to 6 either.
No, it isn't. There have been systems where it was, but it is very
dubiously conforming to Fortran 2003 to use the same unit number for
INPUT_UNIT and OUTPUT_UNIT (what you call the keyboard and screen,
Rubbish! There still are today and will be in the future Fortran
compilers where 0 or "*" used as a unit number mean "screen and
keyboard". Mind you, the very first compilers didn't, but all mine
Exact quote from one of my Fortran manuals
" * represents the keyboard and screen, a sequential formatted file,
also known as unit zero".
And that was the first line in the chapter on files and I/O !!!
You can talk about UNIX and F2003 and so on, but the average just-come-
to-Fortran user won't know and won't care about the exceptions or even
(probably) 2003 and later compiler versions, and not only because so
many cost more that the new computers they are using (shame!).
I certainly don't and there just may be one person reading this Forum
with more years of using Fortran. I'll always grant there are many who
know far more about the current compilers that I don't need to use (I
have Intel 9.0 as my latest).
CVF/DFV and Intel compilers all accept unit 0 or the asterisk as do
all the (Intel-based) compilers. As for the other abbove guidlines of
mine; these are the same suggestions made by many experienced Forum
posters over the years - "don't use 1 to 6 as unit numbers, but
especially not 1 to 3".
And when I sugested not use unit zero, I really meant in the sense of
don't specifically OPEN a file as unit zero (I used unit "0" instead
of "*" by habit until quite recently).
If I ever say something works it's because I'm using it. And youl'd
better believe it's in the manual that goes with the compiler as well.
I doubt if "INPUT_UNIT" appears in any of the Fortran manuals I have -
certainly not in the index of three and the bodies of two (the third
is three inches thick and I'm not disposed to check every one of the
page any further).
Don't nit-pick - try to help the new user!