# Vscode breakpoint not working in callback

**URL:** <https://discourse.julialang.org/t/vscode-breakpoint-not-working-in-callback/78830>\
**Category:** VS Code\
**Tags:** question\
**Created:** [March 31, 2022, 5:42pm UTC](https://discourse.julialang.org/t/vscode-breakpoint-not-working-in-callback/78830 "2022-03-31T17:42:57Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![anon69491625](https://avatars.discourse-cdn.com/v4/letter/a/aeb1de/32.png) [@anon69491625](https://discourse.julialang.org/u/anon69491625)\
**Post date:** [March 31, 2022, 5:42pm UTC](https://discourse.julialang.org/t/vscode-breakpoint-not-working-in-callback/78830/1 "2022-03-31T17:42:57Z")

</div>

I’m a noob and learning how to set up vscode so bear with me please. So I have an asynchronous process that completes a callback successfully. I picked the line where it prints out the message telling me that it’s in the callback.

```julia
  println("historicalData: $reqId $(size(bar))")

```

the println sends output to stdout but the breakpoint does NOT halt the program.

**What am I missing please?**

```julia
d, wrap = Jib.simple_wrap();

wrap.historicalData= function(reqId::Int, bar::DataFrame)

  println(symbols[reqId])

  d[:history] = bar

  println("historicalData: $reqId $(size(bar))")

  println(bar)
  
  
end

```

---

<div class="post-metadata">

**Author:** ![Ross\_Boylan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/ross_boylan/32/9210_2.png) [@Ross\_Boylan](https://discourse.julialang.org/u/Ross_Boylan)\
**Post date:** [March 20, 2023, 4:18am UTC](https://discourse.julialang.org/t/vscode-breakpoint-not-working-in-callback/78830/2 "2023-03-20T04:18:42Z")

</div>

My understanding is that breakpoints outside of the main thread are ineffective, at least in VSCode. I have found that breakpoints don’t fire inside of `Task`s even if julia is running with only 1 thread.