[Project516]

WatchService now works. FileSystems.getDefault().newWatchService() returns the JDK's own LinuxWatchService, and this adds the inotify natives under it. Before this, those natives were missing, so creating a watch service failed.

How it works:

• The VFS tells listeners when it creates, writes, deletes, renames or sets the time of a path (VFS.watchChanges).
• Each inotifyInit gets its own state and an in-VM Sock that receives Linux-format inotify_event records. The JDK's poll, read and socketpair calls work on it like any other socket, so a blocked poller does not stall other threads.
• Renames report the old name as deleted and the new one as created, which is what the JDK makes of IN_MOVED_FROM and IN_MOVED_TO. Removing a watched directory sends IN_IGNORED, so its key becomes invalid. Over 1 MB of queued events sends IN_Q_OVERFLOW, which reports OVERFLOW.
• Relative watch paths resolve against the VM's working directory.

Tests:

• test/java/WatchService.java compares create, modify and delete events with HotSpot.
• 8 OpenJDK tests pass and go into passing.txt: Basic, LotsOfCancels, LotsOfCloses, LotsOfEntries, LotsOfEvents, MayFlies, SensitivityModifier, UpdateInterference.
• pnpm typecheck, pnpm build and pnpm test pass.

Limits, also in docs/support.md:

• Only changes made inside the VM are reported. A file another host program changes produces no event.
• DeleteInterference times out at 120 s: its delete loop finishes, but the test does not end in time. Not in passing.txt.

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Reviewing files that changed from the base of the PR and between 7ca3747 and 78bd09a.

Files selected for processing: 6

• docs/support.md
• src/fs.ts
• src/natives/nio.ts
• src/natives/sockets.ts
• test/java/WatchService.java
• test/jtreg/passing.txt

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[project516-review-bot]

This PR implements WatchService via inotify using an in-VM socket pair. The VFS notifies watchers on create/modify/delete/rename/setMtime; each inotifyInit gets a dedicated Sock that receives Linux-format inotify_event records. The JDK's poll/read/socketpair calls work on this socket. 8 OpenJDK WatchService tests pass. The limitation that only VM-internal changes are reported is documented.

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_{review-bot, model nvidia/nemotron-3-ultra-550b-a55b:free, verdict approve}

[project516-review-bot]

This PR implements WatchService using inotify over a virtual socket. The VFS notifies watchers on create/modify/delete/rename/setMtime; each inotifyInit gets a non-blocking socket that receives Linux-format inotify_event records. Eight OpenJDK tests pass. The implementation correctly handles the happy path but has a few edge-case gaps: non-directory watch returns ENOENT instead of ENOTDIR, watched directory deletion emits only IN_IGNORED (missing IN_DELETE_SELF), nativePath lacks bounds checking, and rename cookie is always zero (though MOVED_FROM/TO are not currently emitted).

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_{review-bot, model nvidia/nemotron-3-ultra-550b-a55b:free, verdict approve}

[project516-review-bot]

This PR implements WatchService using an in-VM inotify emulation. The VFS notifies watchers on create/modify/delete/rename/setMtime; each inotifyInit gets a non-blocking Sock that receives Linux-format inotify_event records. The JDK's poll/read/socketpair calls work on these sockets. Eight OpenJDK WatchService tests pass. Two significant defects remain: nativePath reads native memory without bounds checks, and watched-directory deletion emits only IN_IGNORED without the preceding IN_DELETE_SELF that Linux produces.

Not approved: 3 earlier points are still open in the threads.

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_{review-bot, model nvidia/nemotron-3-ultra-550b-a55b:free, verdict comment}

[project516-review-bot]

The PR implements WatchService by adding a VFS watcher mechanism and an inotify emulation layer over a socket pair. VFS notifies registered callbacks on create, modify, delete, and rename; the native layer translates these into Linux-format inotify events that the JDK's LinuxWatchService consumes. Eight OpenJDK WatchService tests pass. However, the implementation deviates from Linux inotify semantics in ways the passing tests do not cover: IN_DELETE_SELF is not emitted when a watched directory is deleted, the cookie field is always zero (breaking IN_MOVED_FROM/TO correlation), IN_Q_OVERFLOW events use wd=0 instead of -1, and nativePath lacks full address-bounds validation.

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_{review-bot, model nvidia/nemotron-3-ultra-550b-a55b:free, verdict approve}