Thank you, that was what I was looking for. I had forgotten about
deadlines, and I didn't realise that you could change a deadline even while
a read was in progress.
In case it's helpful to anyone, here's a proof-of-concept. It doesn't work
on play.golang.org because of the network communication.
package main
import (
"context"
"fmt"
"io"
"net"
"os"
"time"
)
type ConnWithContext struct {
net.Conn
Ctx context.Context
}
func NewConnWithContext(ctx context.Context, conn net.Conn)
*ConnWithContext {
go func() {
<-ctx.Done()
conn.SetDeadline(time.Now())
}()
return &ConnWithContext{
Conn: conn,
Ctx: ctx,
}
}
func (c *ConnWithContext) Read(b []byte) (n int, err error) {
return c.Conn.Read(b)
}
func main() {
ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
defer cancel()
conn, err := net.Dial("tcp", "smtp.gmail.com:25")
if err != nil {
fmt.Println(err)
return
}
cwc := NewConnWithContext(ctx, conn)
n, err := io.Copy(os.Stdout, cwc)
fmt.Println(n, err)
cwc.Close()
}
--
You received this message because you are subscribed to the Google Groups
"golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to golang-nuts+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/golang-nuts/c7d926b1-7b05-47a0-9eb3-f0e1533b81a6o%40googlegroups.com.
