It took me a bit of time to get this simple program working so I'm sharing for other people new to Go.

package main

import (
    "fmt"
    "io"
    "net"
)

func reader(r io.Reader) {
    buf := make([]byte, 1024)
    for {
        n, err := r.Read(buf[:])
        if err != nil {
            return
        }
        println(string(buf[0:n]))
    }
}

func main() {
    c, err := net.Dial("unix", "/var/run/docker.sock")
    if err != nil {
        panic(err)
    }
    defer c.Close()

    fmt.Fprintf(c, "GET /images/json HTTP/1.0\r\n\r\n")

    reader(c)
}