# How to stop/exit workflow?
**URL:** https://community.seqera.io/t/how-to-stop-exit-workflow/408
**Category:** Ask for help
**Created:** [January 18, 2024, 5:36pm UTC](https://community.seqera.io/t/how-to-stop-exit-workflow/408 "2024-01-18T17:36:41Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@complexgenome](https://community.seqera.io/u/complexgenome)
#### Post date: [January 18, 2024, 5:36pm UTC](https://community.seqera.io/t/how-to-stop-exit-workflow/408/1 "2024-01-18T17:36:41Z")
Hi there,
Is there a way to stop/exit workflow after a process?
For e.g., using exit keyword or something?
```auto
workflow wes {
def csvFile = params.input_csvFile //def csvFile = file($params.input_csvFile)
Channel
.fromPath( csvFile )
.splitCsv( )
.multiMap { row ->
def tumor_reads = tuple( file( row[3]) ,file(row[4]))
def normal_reads = tuple(file(row[1]),file(row[2]) )
tumor:
tuple( row[0], tumor_reads )
normal:
tuple( row[0], normal_reads )
}
.set { samples }
FASTP(samples.tumor, samples.normal)
step2(FASTP.out)
step3(step2.out)
///exit/stop here how do I do?
step4()
step5()
step6()
step7()
step8()
step9()
step10()
}
```
I’d like to stop processing at step3 without commenting out remaining lines.
How do I achieve it?
---
### Author:  [@mribeirodantas](https://community.seqera.io/u/mribeirodantas)
#### Post date: [January 18, 2024, 5:47pm UTC](https://community.seqera.io/t/how-to-stop-exit-workflow/408/2 "2024-01-18T17:47:51Z")
When I’m developing a pipeline and want to see how things are going up to a certain point, I add `return` at the following line, and the pipeline will end there. It’s a useful little trick, though less valuable than live debugging with a fully powered IDE.
When talking about a proper exit during a pipeline run, there’s a Nextflow function specific to that named `error`. It’ll throw an exception. Let’s run the Nextflow pipeline below:
```Groovy
process FOO {
debug true
input:
val x
output:
stdout
script:
"""
echo FOO process ${x}
"""
}
process BAR {
debug true
input:
val x
output:
stdout
script:
"""
echo BAR process ${x}
"""
}
workflow {
Channel
.of(1..4)
.set { my_ch }
FOO(my_ch)
BAR(my_ch)
}
```
The output:
Now, let’s add an `error` call before the line with `BAR(my_ch)`.
```Groovy
...
workflow {
Channel
.of(1..4)
.set { my_ch }
FOO(my_ch)
error("Some issue occurred. A useful message here :)")
BAR(my_ch)
}
```
Output:
As you can see, though, it’s an abrupt error. It doesn’t really care what’s going on, as soon as the `error` call is evaluated, the pipeline is terminated. The best way to handle such situations is to use `errorStrategy` (more info [here](https://www.nextflow.io/docs/latest/process.html#errorstrategy)). As for skipping processes, there’s a snippet I posted earlier today that works out-of-the-box for nf-core pipelines, but can also be made to work in your own pipelines with a bit of work. Check it [here](https://community.seqera.io/t/skipping-processes-in-an-nf-core-pipeline/406).
---
### Author:  [@system](https://community.seqera.io/u/system)
#### Post date: [February 8, 2024, 3:18pm UTC](https://community.seqera.io/t/how-to-stop-exit-workflow/408/3 "2024-02-08T15:18:53Z")
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