Craig A. Berry wrote:
On May 30, 2009, at 12:39 PM, John E. Malmberg wrote:
The lib/file/compare.t test has never been correct for VMS, but the
bugs where mostly hidden until testing on a ODS-5 volume with that
allows filenames with more characters in them than VMS traditionally
allows. This is known as EFS_CHARSET mode.
I think you are right that the test that intentionally has a space in
the filename is not working right in traditional mode. The correct fix
would be to detect whether files with spaces in the name are actually
supported and skip that test if not.
This also exposes that the vmsify() routine in the traditional VMS
mode is not matching how the C library in VMS internally implements
the equivalent function.
There are no explicit vmsify calls in the test, so I don't know what you
are referring to.
I am referring to the internal calls to convert Unix to VMS filenames in
VMS.C which the vmsify() routine is a wrapper for.
The CRTL is discarding space characters found in UNIX format filenames
when converting them to VMS. The code that implements vmsify() does not
do that. If it had, this issue would have been seen before.
It also exposes that the flush() operation is a no-op on the VMS
platform, which is something that needs to be fixed.
I don't think it's working any differently than anywhere else. You may
be getting confused by the fact that calling flush() on a filehandle
only flushes the perlio buffers and does not implicitly do an fflush(),
much less an fsync(), on the underlying file descriptor.
This issue with flush() has shown up before, but the test was modified
to not use that algorithm.
The DECC$FILE_SHARING feature needs to be active for this test to work
when the EFS_CHARSET mode is on. By default DECC$FILE_SHARING is off,
and so far none of the other Perl tests need it enabled, even when in
UNIX compatible mode.
Flushing and file sharing aren't really relevant. When calling
File::Compare::compare with a filename rather than a handle, we just
need to make sure the file is closed first on VMS. That's it.
This test is expecting that the data written to the file by one file
handle can be read by the second file handle while the first file handle
is open.
According to X/Open, the only way to guarantee that is to call a fsync()
call. The IO->flush is the closest thing to that, and when I checked
the source code a while back, I discovered that it was not doing anything.
We should be able to fix Perl on VMS so that this test runs the same way
on VMS as it does on UNIX when the extended file specifications are
active, and the UNIX file sharing mode is set.
For the traditional VMS mode, I think that the test should be modified
or skipped, but for using extended file specifications, the original
algorithm should work.
The last e-mail from Craig that I saw about the initial submission
where he was not sure about the extra diagnostics, but was going to
look it over, and I did not see a response to my more detailed post
about patch and why these diagnostics are needed.
Sorry not to follow up in a timely fashion. I'll try to do better this
time. I have something mostly working that just needs a bit more testing.
Regards,
-John
wb8...@qsl.net
Personal Opinion Only
