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    <p>You can never "handle" dereferencing a null pointer. Once you do this, your program is no longer in a well-defined state, and there is no way to continue deterministically. The only course of action is to <code>terminate()</code>, which the OS will kindly do on your behalf if you have not registered a SIGSEGV handler.</p> <p>The word "error" has several meanings which could possibly be confusing: On the one hand, a function that is unable to perform its expected task may be said to have encountered an "error", and it would be expected to signal this, either through a suitable return value, or by throwing an exception. This behaviour might better be called a <em>failure</em>. A correct program must be prepared to handle all possible ways in which a function may return. On the other hand, there are <em>programming errors</em> which simply lead to an wrong or even an ill-formed program. A correct program must never have any programming errors.</p> <p>For example, <code>malloc()</code> may <em>fail</em> (if it cannot find enough space), which it signals by returning a null pointer, but your program would be in error if it dereferenced the result of <code>malloc()</code> without checking.</p> <p>You can never "catch" or "handle" <em>programming errors</em> with further programming. Instead, a correct program must correctly anticipate and handle all <em>failure conditions</em> of component functions, and recursively a correctly written function must always return in a well-defined manner and signal failure appropriately.</p>
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    1. POHow are runtime errors handled in a C library compiled in C++?
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    1. COBut based on my general debugging, dereferencing a NULL pointer results in an exception. So, with a `catch(...)`, could you not handle it?
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    2. CO@RobertDailey: No. Exceptions are part of deliberate, **correct** progamming. Dereferencing a null pointer is never correct. I will add another paragraph to the post, stay tuned.
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    3. CO@RobertDailey: don't confuse C++ exceptions with CPU exceptions. They are two entirely different things.
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