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    <p>I would caution against this.</p> <p>Internal errors are not recoverable. If you divide by zero or whatever - the program is not recoverable.</p> <p>If you turn a termination handler into something that continues the program running, you can have no assurances of the <strong><em>STATE</em></strong> of the program, and you can just crash and corrupt in different ways later. Imagine that the program was holding some <strong><em>locks</em></strong> or other resources at the time of the termination you diverted, for example!</p> <p>Lets have a nasty example:</p> <pre><code>void log(const char* fmt,...) { lock(logfile); va_args... fvprintf(logfile,fmt,__... &lt;--- this line calls the terminator unlock(logfile); } </code></pre> <p>What happens if you don't terminate the program? What happens to the program the next time someone tries to log something?</p> <p>I cannot emphasise this enough - you should use hooking termination methods for extra logging and such, and nothing else. You should always continue to exit afterwards.</p> <hr/> <p>There is a completely different class of error, that can be intercepted:</p> <p>A lot of APIs communicate with the caller using return codes to signal error conditions. It is appropriate to use macros or helper functions to check these return codes and translate them into exceptions. This is because that choice is in your code where you can see it.</p> <p>If you override the _set_errno handler or something, you'd cause code you hadn't wrote that expected the setter to return normally to not return, and it might not have completed its cleanup.</p>
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    1. POHow to handle all errors, including internal C library errors, uniformly
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    1. COBut you may simply want to translate the error (say, to a standard exception) rather than dealing with various other error handling mechanisms.
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    2. COThanks, but some internal errors are recoverable, for the same reason that any error can be recoverable. If someone gives me a string and I use it as format string, and it has a % in it, then, to be sure, I should have checked that, but the program should not have to fail on printf/sprintf--what might just be the printing of a message. Many request-response oriented apps can fail on a single loop but then continue. As for error return codes -- the mentioned errors do not return error codes, but just terminate the program.
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    3. COJoshua, you absolutely should have checked that; that's a classic security breach.
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