# Stdout not defined

**URL:** <https://community.seqera.io/t/stdout-not-defined/2213>\
**Category:** Ask for help\
**Tags:** vscode\
**Created:** [June 23, 2025, 11:26am UTC](https://community.seqera.io/t/stdout-not-defined/2213 "2025-06-23T11:26:53Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![Poshi](https://dub1.discourse-cdn.com/flex013/user_avatar/community.seqera.io/poshi/32/1126_2.png) [@Poshi](https://community.seqera.io/u/Poshi)\
**Post date:** [June 23, 2025, 11:26am UTC](https://community.seqera.io/t/stdout-not-defined/2213/1 "2025-06-23T11:26:53Z")

</div>

I have a working pipeline that contains a process that captures the standard output.  
With the latest language server update in VSCode, it started complaining:

```auto
process DDBB_START {
    input:
        tuple val(meta), val(reads)
    output:
        tuple val(meta), val(reads), stdout

```

the error I see is:

```auto
`stdout` is not defined

```

According to the [documentation](https://www.nextflow.io/docs/latest/process.html#standard-output-stdout), this is the proper way to use it so… what should I do?

---

<div class="post-metadata">

**Author:** ![bentsherman](https://dub1.discourse-cdn.com/flex013/user_avatar/community.seqera.io/bentsherman/32/52_2.png) [@bentsherman](https://community.seqera.io/u/bentsherman)\
**Post date:** [June 23, 2025, 2:06pm UTC](https://community.seqera.io/t/stdout-not-defined/2213/2 "2025-06-23T14:06:56Z")

</div>

Thanks for reporting. I will look into it and see if we can correct it in the compiler. In the meantime, I think you can specify it as `stdout()` and it will work.

---

<div class="post-metadata">

**Author:** ![Poshi](https://dub1.discourse-cdn.com/flex013/user_avatar/community.seqera.io/poshi/32/1126_2.png) [@Poshi](https://community.seqera.io/u/Poshi)\
**Post date:** [June 25, 2025, 9:02am UTC](https://community.seqera.io/t/stdout-not-defined/2213/3 "2025-06-25T09:02:44Z")

</div>

Yes, using `stdout()` gets rid of the error. I will believe that it will work in the same way 🙂 Thanks!

---

<div class="post-metadata">

**Author:** ![bentsherman](https://dub1.discourse-cdn.com/flex013/user_avatar/community.seqera.io/bentsherman/32/52_2.png) [@bentsherman](https://community.seqera.io/u/bentsherman)\
**Post date:** [June 25, 2025, 5:17pm UTC](https://community.seqera.io/t/stdout-not-defined/2213/4 "2025-06-25T17:17:52Z")

</div>

Correction – it turns out that `stdin` and `stdout` cannot be used with parens if they are in a tuple as in your example. If you try to use parens there it will fail.

I have submitted a fix which will allow you to use them without parens: [Fix false error when using stdin/stdout in a tuple by bentsherman · Pull Request #6219 · nextflow-io/nextflow · GitHub](https://github.com/nextflow-io/nextflow/pull/6219)

---

<div class="post-metadata">

**Author:** ![Poshi](https://dub1.discourse-cdn.com/flex013/user_avatar/community.seqera.io/poshi/32/1126_2.png) [@Poshi](https://community.seqera.io/u/Poshi)\
**Post date:** [June 26, 2025, 10:00am UTC](https://community.seqera.io/t/stdout-not-defined/2213/5 "2025-06-26T10:00:47Z")

</div>

OK, removing the parens. I didn’t managed to test them yet. Thanks!

---

<div class="post-metadata">

**Author:** ![system](https://dub1.discourse-cdn.com/flex013/user_avatar/community.seqera.io/system/32/2402_2.png) [@system](https://community.seqera.io/u/system)\
**Post date:** [July 3, 2025, 10:01am UTC](https://community.seqera.io/t/stdout-not-defined/2213/6 "2025-07-03T10:01:30Z")

</div>

This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.