Named pipes with O_NONBLOCK still block

main.go

package main

// go version go1.22.1 darwin/arm64
// M1 2020 macbook with OS version 12.5 (21G72)

import (
	"fmt"
	"os"
	"syscall"
	"time"
)

func main() {
	syscall.Mkfifo("p.pipe", 0666)

	go func() {
		pipe, _ := os.OpenFile("p.pipe", os.O_WRONLY|os.O_APPEND, os.ModeNamedPipe)
		for range 5 {
			pipe.WriteString("Hello\n")

			// Removing this Sleep() DOES NOT cause this bug
			time.Sleep(1000 * time.Millisecond)
		}
		err := pipe.Close()
		fmt.Println("Writer closed pipe", err)
	}()

	pipe, err := os.OpenFile("p.pipe", os.O_RDONLY|syscall.O_NONBLOCK, os.ModeNamedPipe)
	fmt.Println("Opening pipe", err)

	buf := make([]byte, 1)
	for {
		// This should loop infinitely, even after the writer closes the pipe
		fmt.Println("About to read...")

		// After the pipe is closed, this call blocks BUT IT SHOULD NOT.
		n, err := pipe.Read(buf)

		fmt.Println("Read from pipe", n, err)
	}

}