In any case, there will be no talking if the parent would need to trust you but doesn't. That doesn't help kids.
You can't change the law, but you can avoid having identity information to report. Parts of the solution probably involve non-attributable cryptocurrency and tor browsers.
Both "danger" and "abuse" are open for interpretation, and some people take "better safe than sorry" to an unhealthy extreme. Your response suggests to me that this is the case with you.
Even if there is a problem, how is it not better to address that? If the parents don't feel safe, they will avoid all those service providers. The kids don't get help if using the service providers is too risky for the parents.
This is why only a fool would use the service for real problems.
If you can find a way out of that, for example by avoiding knowledge of identity, the service could be safe to use. Maybe you could take payment in a privacy-protecting cryptocurrency (not Bitcoin) and have the users connect with a tor browser.
You can safely use gets on trusted input. For example, your program might create a pipe or socketpair to communicate between the processes that result from a call to fork. The stdout of one process feeds into the stdout of the other process.
Unless you have an insane gets implementation that writes the bytes backwards, you can also safely use it on untrusted input. Simply place a guard page at the end of the buffer. You can do the call from a forked child that you let die, taking notice of the problem in the parent. On systems without threading (because of locks in libc) you can do a longjmp to recover.
No, normally what people desire of a fixed-point representation is a subset of a floating-point representation. Most fixed-point stuff is prototyped as floating-point, then painfully converted into a mess of nasty macros. Ideally there would be assertions to protect against failure due to the limited functionality of the fixed-point type, but probably you don't bother.
It's not maintainable.
We should be able to take that prototype, mark it up with hints for the compiler, and then build with fixed-point enabled.
I'd rather see the ability to place an attribute on a floating-point variable that would inform the compiler that fixed-point might be suitable. You'd specify the requirements that need to be met, and the compiler would choose the fastest format for the current architecture. That format could be fixed-point, decimal float, IEEE float, or something weirder.
For example, your requirements could include: minimum magnitude, maximum magnitude, minimum value, maximum value, maximum additive error, maximum multiplicative error, signed zero needed or not, NaN signed/unsupported/unsigned, infinity distinct from NaN and/or the largest number, etc.
You say what you need for correctness, and the compiler makes it happen.
In any case, there will be no talking if the parent would need to trust you but doesn't. That doesn't help kids.
You can't change the law, but you can avoid having identity information to report. Parts of the solution probably involve non-attributable cryptocurrency and tor browsers.