[Bug libfortran/89020] close(status='DELETE') does not remove file

[robison at arlut dot utexas.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89020

--- Comment #4 from Luke Robison <robison at arlut dot utexas.edu> ---
> First, what virtualbox is doing is a violation of common UNIX
> semantics, so we would be within our rights :-) to do this.

Agreed.  This is definitely outside of the norm for a unix
filesystem.  I just tried this program on windows native
with mingw-64's gfortran, and the file is deleted as expected.
I don't know enough about mingw-64 to know if they've rewritten
that part of the library, or how they translate those system
calls.

> On the third hand, I seem to remember that unlink / close also
> used to cause (potential?) issues with NFS.
I haven't experienced this yet, although I've been using primarily
lustre network mounts, not NFS.

> Work around for virtualbox might be
>     call execute_command_line("rm -f " // filename)

I'm using the (GNU Extension) unlink() function as my work-around.
It isn't strictly Fortran2008, but it is supported by both gfortran
and ifort, so it's good enough for me. (I sure appreciate some of
those highly-compatible extensions, they make my life easier!)