> For the complete documentation index, see [llms.txt](https://docs.urbit.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.urbit.org/urbit-os/base/threads/examples/gall/stop-thread.md). # Stop Thread Here's an example agent with an extra card in `+on-poke` to stop the thread and a little extra in `+on-agent` to print things for demonstrative purposes. We run the thread by poking Spider directly because we need to know the thread ID in order to stop it. In this example we use a thread file, but an inline thread could also be used.

/app/thread-starter.hoon code

{% code title="/app/thread-starter.hoon" lineNumbers="true" %} ```hoon /+ default-agent, dbug =* card card:agent:gall %- agent:dbug ^- agent:gall |_ =bowl:gall +* this . def ~(. (default-agent this %|) bowl) :: ++ on-init on-init:def ++ on-save on-save:def ++ on-load on-load:def ++ on-poke |= [=mark =vase] ^- (quip card _this) ?+ mark (on-poke:def mark vase) %noun ?+ q.vase (on-poke:def mark vase) (pair term term) =/ tid `@ta`(cat 3 'thread_' (scot %uv (sham eny.bowl))) =/ ta-now `@ta`(scot %da now.bowl) =/ start-args [~ `tid byk.bowl(r da+now.bowl) p.q.vase !>(q.q.vase)] :_ this :~ [%pass /thread/[ta-now] %agent [our.bowl %spider] %watch /thread-result/[tid]] [%pass /thread/[ta-now] %agent [our.bowl %spider] %poke %spider-start !>(start-args)] [%pass /thread/updates/[ta-now] %agent [our.bowl %spider] %watch /thread/[tid]/updates] [%pass /thread-stop/[ta-now] %agent [our.bowl %spider] %poke %spider-stop !>([tid %.y])] == == == ++ on-watch on-watch:def ++ on-leave on-leave:def ++ on-peek on-peek:def ++ on-agent |= [=wire =sign:agent:gall] ^- (quip card _this) ?+ -.wire (on-agent:def wire sign) %thread ?+ -.sign (on-agent:def wire sign) %poke-ack ?~ p.sign %- (slog leaf+"Thread started successfully" ~) `this %- (slog leaf+"Thread failed to start" u.p.sign) `this :: %fact ?+ p.cage.sign (on-agent:def wire sign) %thread-fail =/ err !< (pair term tang) q.cage.sign %- (slog leaf+"Thread failed: {(trip p.err)}" q.err) `this %thread-done ?: =(*vase q.cage.sign) %- (slog leaf+"Thread cancelled nicely" ~) `this =/ res (trip !<(term q.cage.sign)) %- (slog leaf+"Result: {res}" ~) `this %update =/ msg !< tape q.cage.sign %- (slog leaf+msg ~) `this == == %thread-stop ?+ -.sign (on-agent:def wire sign) %poke-ack ?~ p.sign %- (slog leaf+"Thread cancelled successfully" ~) `this %- (slog leaf+"Thread failed to stop" u.p.sign) `this == == ++ on-arvo on-arvo:def ++ on-fail on-fail:def -- ``` {% endcode %}

We've added a `sleep` to the thread to keep it running for demonstration: {% code title="/ted/test-thread.hoon" lineNumbers="true" %} ```hoon /+ *strandio |= arg=vase =/ m (strand:rand ,vase) ^- form:m ;< =path bind:m take-watch ;< ~ bind:m (send-raw-card [%give %fact ~[path] %update !>("message 1")]) ;< ~ bind:m %- send-raw-cards :~ [%give %fact ~[path] %update !>("message 2")] [%give %fact ~[path] %update !>("message 3")] [%give %fact ~[path] %update !>("message 4")] == ;< ~ bind:m (send-raw-card [%give %kick ~[path] ~]) ;< ~ bind:m (sleep ~m1) |= strand-input:rand ?+ q.arg [~ %fail %not-foo ~] %foo [~ %done arg] == ``` {% endcode %} Save these, `|commit`, and run with `:thread-starter [%test-thread %foo]`. You should see: ``` Thread started successfully message 1 message 2 message 3 message 4 Thread cancelled successfully Thread cancelled nicely ``` Now, try changing the vase in our new card from `!>([tid %.y])` to `!>([tid %.n])`. Save, `|commit`, and run again. You should see: ``` Thread started successfully message 1 message 2 message 3 message 4 Thread cancelled successfully Thread failed: cancelled ``` ### Analysis The card we've added to our agent: ```hoon [%pass /thread-stop/[ta-now] %agent [our.bowl %spider] %poke %spider-stop !>([tid %.y])] ``` ...pokes spider with mark `%spider-stop` and a vase containing the tid of the thread we want to stop and a `?`. The `?` specifies whether to end it nicely or not. If `%.y` it will end with `%thread-done` and a `*vase` bunted vase. If `%.n` it will end with `%thread-fail` and a vase containing `[term tang]` where `$term` is `%cancelled` and `$tang` is `~`. You can see the difference in our tests above. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.urbit.org/urbit-os/base/threads/examples/gall/stop-thread.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.