[Bug libfortran/65200] Handle EPERM when opening files

[jvdelisle at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65200

Jerry DeLisle <jvdelisle at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jvdelisle at gcc dot gnu.org

--- Comment #2 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> ---
>From PR65203 Thomas comment:

Currently, when encountering EACCES or EROFS upon opening, we fall back towards
opening the file read-only.

This is

a) not documented
b) surprising for some users (an inconsistency has been commented upon)
c) causes inconsistencies with NFS v4, which appears to return EPERM for a
read-only file for no reason that I can see.

The original report can be found at
http://stackoverflow.com/questions/28696539/fortran-open-call-differs-on-nfsv3-vs-nfsv4
.

My suggestion would be to a) document and c) extend the behavior to EPERM.