[Bug fortran/60596] Inquire size for stream zero

[sgk at troutmask dot apl.washington.edu]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60596

--- Comment #3 from Steve Kargl <sgk at troutmask dot apl.washington.edu> ---
On Thu, Mar 20, 2014 at 02:27:15AM +0000, patnel97269-gfortran at yahoo dot fr
wrote:
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60596
> 
> --- Comment #2 from patnel97269-gfortran at yahoo dot fr ---
> Using your program, I get the same behavior I describe . 
> 
> Running  with gfortran I get ./a.out < tmp.dat 
>          400
>            0
>            0
> 
> Running with ifort I get  ./a.out < tmp.dat 
>          400
>            0
>          400
> 
> Why the size the shell input is 0 ?
> 

Because this line of code:

  close(input_unit)

has closed the input_unit.  This closes the stdin stream.
input_unit is simply a integer and is commonly the value 
of 5.  The next line now opens unit=input_unit and because
you have not specified a file= tag in the open statement

  open(unit=input_unit, access='stream')

you now have a file named 'fort.5'.  You have not written
anything into fort.5 so it of course has a file size of
0.

  inquire(unit=input_unit,size=sz)

This line of code retrieves the file size from the OS.

  print *, sz

and this one displays.

  close(input_unit)

I have no idea why ifort is reporting 400 for the last bit
of code.  It looks like a bug in ifort to me.