RFR: 8375294: (fs) Files.copy can fail with EOPNOTSUPP when copy_file_range not supported

[Alan Bateman]

On Thu, 15 Jan 2026 06:52:24 GMT, Jaikiran Pai <jpai at openjdk.org> wrote:

> Hello Brian, the change looks good to me. Interestingly `man copy_file_range` doesn't make a mention of this `errno`. 

I was chatting with Brain yesterday about this as EOPNOTSUPP doesn't seem to have originally listed in the Linux man page. It does list is now. It does not list ENOTSUP (which as you note has the same value on Linux). Right now, the usage is in Linux specific code. If it were to move to the "unix" tree for use by other Unix platforms then I think the possible errors would need to be double checked.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/29234#issuecomment-3753250259