Revert "IO: switch Win32 pipes to `PIPE_WAIT` and use a sentinel byte"#891

compnerd merged 1 commit intoswiftlang:release/6.2swiftlang/swift-corelibs-libdispatch:release/6.2from

z2oh:revert-866-6.2-pipesz2oh/swift-corelibs-libdispatch:revert-866-6.2-pipesCopy head branch name to clipboard