Comment by za_creature
2 days ago
This specific library call is quite poorly designed.
Standard C api calls return an integer, which is 0 on success or nonzero on error. Ignoring it is an intentional choice. `errno` is the hack that shouldn't really exist because it's trivially easy to forget to check that and also has issues with threading (patched by making it a thread local) and more recently, coroutines (which admit no general purpose patch because they're a userspace construct).
Another reason why this is terrible is that it's unclear what the returned pointer's lifetime is. Is it until the next call to crypt? If so, is it thread-local like errno? If it's passed on to the user, is it safe to call free() on it, or is there a crypt_free function that should be called instead?
But all of this, and I mean all of it pales in comparison to returning '*' on error.
> But all of this, and I mean all of it pales in comparison to returning '*' on error.
100% agree. This is an egregious failure. But C's error-handling story would be bad even without this, and the badness of C's error handling is what motivated the (bad) decision to return *.
It'd be great if we wrote systems software in a language that supported advanced features like...
checks notes
...returning multiple values.
Hell, even in VBA you had to at least spend the keystrokes to type "on error resume next".
It's just that every other string than "*" would have been a better choice, including even the empty string (which would have been the next terrible choice).