v3.1.1

• Pin the ConPTY NuGet package to 1.25.260930003 rather than resolving
  latest at build time, so an upstream ConPTY release can no longer change
  what the wheels contain without a pywinpty release.
• Require winpty-rs 1.0.7, which fixes three user-facing bugs: a teardown
  deadlock against ConPTY 1.25 that made closing a PTY hang and left the child
  process orphaned, the loss of the first argument on the WinPTY backend, and
  PTY.write() returning 0 for payloads the child received in full.
• Correction, 2026/10/28. These notes originally claimed that large ConPTY
  output was no longer truncated after the child exits, and that such output
  now reaches EOF. Both halves were wrong and nothing in 3.1.1 changed either.
  The truncation reported in
  #565 is
  cpython#86210, where an
  unbuffered _textiowrapper_writeflush ignores a partial write and silently
  drops the remainder - a producer-side CPython bug, not a pywinpty one. The
  measurement behind the original claim used a buffered producer writing
  line-sized chunks, so it never exercised the reported condition. EOF
  detection was also still broken on the ConPTY backend in 3.1.1:
  PTY.iseof() could never return True. That half is fixed in 3.1.2 by
  winpty-rs 1.0.8; the CPython bug remains upstream.
• Stop publishing the vendored NuGet CPython inside the source distribution.
  The 3.0.5 and 3.1.0 sdists were ~16.2 MB because the pythonarm64 NuGet
  install landed in the same checkout that maturin sdist archives, and
  twine check never inspects archive contents. The sdist is back to ~30 KB
  and a content check now gates the upload.

Issues Closed

• Issue 518 - Arguments to the WinPTY backend don't work (PR 591)

In this release 1 issue was closed.

Pull Requests Merged

• PR 591 - Require winpty-rs 1.0.7, by @andfoy (518)
• PR 590 - Pin the ConPTY NuGet version, by @andfoy

In this release 2 pull requests were closed.