Should I set errno?

Question

I\'m writing a module which exports an interface similar to send and recv.

Since those functions are supposed to return respectively the nu

Answer 1

You can just assign a value to errno, but keep in mind that there are other ways to signal an error which, depending on your situation, may be more suitable:

1. Do not return the number of bytes read, but instead have an output parameter with type int * (or size_t * or whatever you use). You can then return an error code.
2. Assuming that your return type is a signed type and that a negative sent or received amount of bytes does not make sense, use negative values to signal the respective error conditions.