On 20/01/2017 20:37, Peter Levart wrote:
I guess the JmodTask is creating a temp file because it wants the file
to not be observed by other processes while it is being written to,
right? At the end when the tempTarget is fully written, it is renamed
to its intended name with:
Files.move(tempTarget, target);
...but that operation will not be atomic since you didn't pass
ATOMIC_MOVE to the CopyOption... options. Even if you did, the atomic
move will succeed only when both tempTarget and target point to the
same filesystem. Since you are creating tempTarget in default
temporary files location (/tmp on UNIXes) this might not be the case
(depending on where the real target is located).
So why don't you simply append a .tmp suffix to the intended target
file name when opening the JmodOutputStream. This would ensure the
file location will be on the same filesystem as the final target name
as it will be created in the same directory. Module path scanning
should skip files with .tmp extension then.
Module path scanning doesn't skip unrecognized files, this is because it
allows for implementation specific packaging formats.
Mandy - a while back then Erik changed the build so that JMOD files are
created in JMODS_TEMPDIR rather than JMODS_DIR. I think this was to
reduce interference with concurrent execution of the `jmod` tool. This
might mean you can avoid using /tmp.
-Alan.
