Delve: Can't get headless mode to work with client

[primalmotion]

1. What version of Delve are you using (dlv version)?

Delve Debugger
Version: 1.0.0-rc.1
Build: 5c9b2009cab214c1f912a2d8c6c89eec9f3ada2b

But I also tried 0.12.1 and HEAD

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

go version go1.9.1 darwin/amd64

1. What operating system and processor architecture are you using?
   macOS High Sierra 10.13 (17A405)

2. What did you do?
   I have this little demo program

package main

import (
    "flag"
    "fmt"
    "os"
    "os/signal"
    "time"
)

func main() {
    var mode string
    flag.StringVar(&mode, "mode", "1", "mode")
    flag.Parse()

    switch mode {
    case "1":
        f1()
    case "2":
        f2()
    case "3":
        f3()
    }
}

func f1() {
    fmt.Println("runing mode 1")
    go func() {
        for range time.Tick(1 * time.Second) {
            fmt.Println("ping")
        }
    }()

    c := make(chan os.Signal, 1)
    signal.Notify(c, os.Interrupt)
    <-c
}

func f2() {
    fmt.Println("runing mode 2")
    go func() {
        for range time.Tick(1 * time.Second) {
            fmt.Println("ping")
        }
    }()

    for range time.Tick(10 * time.Second) {
    }
}

func f3() {
    fmt.Println("runing mode 3")
    for range time.Tick(1 * time.Second) {
        fmt.Println("ping")
    }
}

Then I start delve by doing in a terminal

$ dlv debug --headless --listen :2345 --log  -- -mode=1 # mode 1, 2 or 3 actually end up not working the same
2017/10/06 13:38:08 server.go:73: Using API v1
2017/10/06 13:38:08 debugger.go:97: launching process with args:[/Users/tonio/Documents/Aporeto/workspace/code/go/src/github.com/aporeto-inc/test/debugger/debug -mode=1]
API server listening at: [::]:2345

Then I connect from another terminal:

$ dlv connect 127.0.0.1:2345
Type 'help' for list of commands.
(dlv)

So far so good. Now if I type c the program starts, but I never get the possibility to to anything else until I CTRL-C the dlv client

Here is a little gif

I did this reduction as I was using VSCode and realized that the headless server never responds to the client.

1. What did you expect to see?
   stuff

2. What did you see instead?
   no stuff

[aarzilli]

Yes, you can not interact with the target process unless it's stopped.

[primalmotion]

I can't even pause the process. So I have to plan all my breakpoints before I start delve?

[ayush987goyal]

Facing the same issue. Not able to add breakpoints post launching. Is there a workaround/fix for this?