{
  "$type": "site.standard.document",
  "bskyPostRef": {
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    "uri": "at://did:plc:ivbknywyskln22er3nkssdhl/app.bsky.feed.post/3mh2wdxnbjxv2"
  },
  "path": "/t/idea-add-an-option-to-set-the-mode-to-fs-copy/24080#post_8",
  "publishedAt": "2026-03-14T22:48:52.000Z",
  "site": "https://internals.rust-lang.org",
  "tags": [
    "`NtCopyFileChunk`",
    "Linux's `copy_file_range` also doesn't do the whole job and doesn't work in all cases"
  ],
  "textContent": "chrisd:\n\n> On Windows ... there's no single function to copy using file handles ... there are some low-level functions which can help, such as `NtCopyFileChunk`, but [it doesn't do the whole job and] doesn't work in all cases ...\n\nLinux's `copy_file_range` also doesn't do the whole job and doesn't work in all cases; callers need to check for a \"can't do it this time\" error return and fall back to a manual copy loop. It sounds like the Windows implementation of `io::copy` might usefully be taught to use `NtCopyFileChunk` if it doesn't already, but `fs::copy` on Windows should keep using `CopyFile`, would you agree?",
  "title": "Idea: Add an option to set the mode to fs::copy"
}