Fix stdin over-read on seekable inputs - #14077
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pchickey
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Aug 5, 2026
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Fixes #14065.
Avoid using
std::io::Stdin's process-global buffer in the stdin worker because it can advance redirected seekable input beyond the number of bytes requested by a guest.Use unbuffered OS reads on Unix and non-console Windows input while retaining
StdinLockto preserve serialization with other process users. Add a subprocess regression test that reads one byte and verifies that theshared file offset advances by exactly one byte.