How is C code tested (need examples)?

Question

Software testing

In general, in a nutshell:
I am a complete lamer, and not a programmer. I am involved in one open source project written in C, and I am tired of multiple broken features in the development of the project. And every time they break the same thing.
I heard that testing helps to check all this, and if something is wrong, you can figure it out at the automatic testing stage and fix the bug, or understand that something went wrong.
The essence of the problem:
I don’t know how it’s done at all, I would like a couple of examples from live projects how they test the code, how it generally looks, and how they are written. I would be very grateful to anyone who can help with examples.
Thank you.

Answer 1

stackoverflow.com/questions/65820/unit-testing-c-code
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