[go-nuts] go log.Println(http.ListenAndServe(...)) blocks

[Christoph Berger]

Hi gophers, 

I hope someone can help finding out why a particular goroutine call can 
block the main goroutine.

In the following code, all "go" calls spawn off a goroutine and return as 
expected, except for the last one that blocks the main goroutine. 

Is this a bug, or am I missing something subtle or even obvious (obvious to 
all others only of course)?

package main

import (
        "log"
        "net/http"
)

func main() {
        // all of these work as expected
        go http.ListenAndServe("localhost:8080", nil)
        go log.Println("goroutine")
        go func() {
                log.Println(http.ListenAndServe("localhost:8081", nil))
        }()

        // The following line blocks the main goroutine.
        go log.Println(http.ListenAndServe("localhost:8082", nil))

        log.Println("after go log.Println(http.ListenAndServe())") // never 
prints
        select {} // remove this, and the code still never finishes
}

All three servers eventually run (try curl localhost:8080; curl 
localhost:8081; curl localhost:8082),

In the playground <https://go.dev/play/p/vObgGGM7MJD>, the code even 
deadlocks. 

Any idea?

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