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Comment by majke | Hacker News Reader

My fav little-known trick is to test various syscalls fail with strace fault injection, like:

  $ strace -e trace=clone -e fault=clone:error=EAGAIN

random link: https://medium.com/@manav503/using-strace-to-perform-fault-i...

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This is incredible and something I’d wish I’d known about a long time ago. I’d often stub out functions like this knowing I couldn’t test the failure branch, but try to limit that to as small an area as possible.

Thanks!

You might also like https://github.com/eradman/entr

This is great. Anyone know of an equivalent in Windows?

Application Verifier provides fault injection, as well as detection for a bunch of conditions (https://learn.microsoft.com/en-us/windows-hardware/drivers/d...).

It's only intended for native/unmanaged code though.

The recommended approach for managed apps (meaning .NET) is probably dependency injection. If you want to test a component with fallible methods, write an interface wrapper and inject a fallible mock. The JIT will do dynamic PGO and devirtualize in normal application usage.

Dtrace can do the same and much more I believe with destructive actions, and it is supported on Windows.

And OpenBSD? :D

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