Sentinel Errors

Lesson in the Go Roadmap · Stage 22: Using 3rd Party Packages

Last updated 14 September 2026

What is Sentinel Errors?

Predefined error values representing specific conditions, defined as package-level variables. Check using errors.Is() or direct comparison. Examples: io.EOF. Enable predictable APIs where callers handle specific errors differently.

Study this in the interactive course See the whole Go roadmap

Free resources to learn Sentinel Errors

ArticleGolang Sentinel Error
ArticleWriting Clean Code in Go: Sentinel Errors

Sentinel Errors: common questions

Can I learn Sentinel Errors in Hindi?

This lesson is written in English. Once you sign in, open it in the interactive course and ask the AI tutor to explain Sentinel Errors in Hindi or Hinglish. The tutor answers from this lesson’s own text, so it stays on the syllabus, and it runs on your own Google, OpenAI or Anthropic key.

Is this Sentinel Errors tutorial for beginners?

It is lesson 87 of 172 in the free Go roadmap, in stage 22, Using 3rd Party Packages. If you are new to Go, start from stage 1 and come back here in order; if you already know the earlier stages, this lesson stands on its own.