What version of Go are you using (go version)?

1.6.2 and 1.4.3

What operating system and processor architecture are you using (go env)?

linux, amd64

What did you do?

Minimal example server (main.go):

package main

import (
    "log"
    "net/http"
    "time"
)

func main() {
    log.Fatal(http.ListenAndServe(":9999", http.TimeoutHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    }), time.Second, "timeout")))
}

Then:

go run main.go
curl -i "http://127.0.0.1:9999"

What did you expect to see?

I expect 200 OK because it is consistent with the default behavior without the TimeoutHandler.

HTTP/1.1 200 OK
.......

What did you see instead?

HTTP/1.1 0 status code 0
......

Solution

In func (h *timeoutHandler) ServeHTTP in net/http/server.go, change the code from:

w.WriteHeader(tw.code)

To:

if tw.code == 0 {
    tw.code = StatusOK
}
w.WriteHeader(tw.code)