fix: /dev/ptmx leak on macOS #882
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This was referenced Jan 28, 2026
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Tyriar
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dmitrivMS
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speakman
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Feb 10, 2026
node-pty v1.1.0 has an off-by-one bug in pty_posix_spawn() on macOS where low_fds[0] (allocated via posix_openpt()) is never closed due to a buggy cleanup loop (`count > 0` vs the correct `i <= count`). This leaks 1 PTY master fd per pty.spawn() call, eventually exhausting all 511 PTY pairs on macOS (kern.tty.ptmx_max). Upstream fix: microsoft/node-pty#882 (merged 2026-01-28). Also fixes the abort handler to kill the entire process group (-pid) with SIGTERM instead of sending SIGHUP to just the launcher PID, ensuring the Claude binary grandchild is also terminated.
This was referenced Feb 10, 2026
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For microsoft/vscode#182212
The ptmx leak was from
low_fds[0]that was always opened and never closed. Drive by improvement for error propagation and failure case cleanups.