# Why Does ParaView Documentation Reverse the Conventional Return Codes for Success and Failure?

**URL:** https://discourse.paraview.org/t/why-does-paraview-documentation-reverse-the-conventional-return-codes-for-success-and-failure/14442
**Category:** ParaView Support
**Created:** [April 19, 2024, 4:44pm UTC](https://discourse.paraview.org/t/why-does-paraview-documentation-reverse-the-conventional-return-codes-for-success-and-failure/14442 "2024-04-19T16:44:53Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Reshm\_R\_S](https://discourse.paraview.org/user_avatar/discourse.paraview.org/reshm_r_s/32/12131_2.png) [@Reshm\_R\_S](https://discourse.paraview.org/u/Reshm_R_S)
#### Post date: [April 19, 2024, 4:44pm UTC](https://discourse.paraview.org/t/why-does-paraview-documentation-reverse-the-conventional-return-codes-for-success-and-failure/14442/1 "2024-04-19T16:44:53Z")

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I am quite used to the convention of representing a “success” with “return 0” and “failure” with “return 1”.  
Do you know why this concept is reversed in the documentation at [util.vtkAlgorithm Module — ParaView/Python 5.12.0-776-gfc5a2391cc documentation](https://kitware.github.io/paraview-docs/latest/python/paraview.util.vtkAlgorithm.html) ?  
If I am correct, the examples you provide uses “return 1” for “success” and “return 0” for “failure”, which is confusing to me.  
Please comment.

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### Author: ![ben.boeckel](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.paraview.org/u/ben.boeckel)
#### Post date: [April 19, 2024, 5:01pm UTC](https://discourse.paraview.org/t/why-does-paraview-documentation-reverse-the-conventional-return-codes-for-success-and-failure/14442/2 "2024-04-19T17:01:54Z")

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VTK’s own API uses the “reverse” convention. ParaView inherits that. I believe that the original development was on Windows quite a bit where the APIs are indeed “0 for failure” a lot of the time.