scouten
The following code …
GenStage.sync_subscribe(cons, to: prod)
IO.puts "line 108"
# Wait for process to exit.
Process.monitor(cons)
receive do
{:DOWN, _ref, :process, ^cons, :normal} ->
:ok
{:DOWN, _ref, :process, ^cons, reason} ->
Process.exit(self, reason)
end
… crashes with ** (EXIT from #PID<0.672.0>) no process but only if the IO.puts call is present. If I comment it out, the code runs as intended and the corresponding tests pass.
Any ideas how that could be causing it?
Where Next?
Trending in Questions
Other Trending Topics
Latest on Elixir Forum
Sponsor Spotlight
Elixir, Erlang & messaging conferences from Code Sync. Next up: ElixirConf US (10–11 Sep) & Code BEAM Europe (21–22 Oct), Haarlem + online.
Categories:
Sub Categories:
Forums
Popular Tags
- #ecto
- #liveview
- #troubleshooting
- #learning-elixir
- #library
- #deployment
- #erlang
- #testing
- #genserver
- #mix
- #absinthe
- #remote-other
- #otp
- #plug
- #how-to-question
- #macros
- #postgres
- #elixirconf
- #channels
- #exunit
- #discussion
- #code-sync
- #podcasts
- #javascript
- #onsite
- #dialyzer
- #docker
- #authentication
- #umbrella
- #full-time-contract
- #podcasts-by-brainlid
- #ecto-query
- #ai
- #elixirconf-us
- #blog-post
- #elixir-ls
- #phoenix_html
- #iex
- #graphql
- #genstage
- #websockets
- #supervisor
- #advent-of-code
- #distillery
- #processes
- #api
- #forms
- #elixirconf-eu
- #metaprogramming
- #hex
Our Sponsors
Build Elixir applications with speed and confidence.
Supporting innovation across the BEAM ecosystem.
Catch errors, track performance, monitor hosts and more.
Error tracking, logs, uptime, and Just Enough APM. Built for developers.
Elixir, Erlang & BEAM conferences from Code Sync - join us in 2026!
Practical resources that improve the lives of professional developers.
Master modern tools, write cleaner code, and tackle real-world challenges.
**Building the future of software with AI, trust, and human connection.**
The team behind Membrane, Popcorn, LiveDebugger. Available for hire.
Courses that'll move you from confusion to "Aha, now I get it!"
Showing Posts 1 to 1- Show Best Posts
- Show All (oldest first)
- Show All (newest first)
scouten
Answering my own question after further debugging: It looks like a race condition.
If I flip the order of
IO.putsandProcess.monitor, the crash goes away. So I suspect the consumer may be dying during the timeIO.putsis running.