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    <p>Not throwing exceptions in your own code is relatively easy: you just don't use the <code>throw</code> statement.</p> <p>Not throwing exceptions from memory allocation failures is a little more painful: either you don't use normal <code>new</code> (use <code>new(std::nothrow)</code> or <code>malloc</code> or something instead), or you use some nonstandard compiler option to get it to do something nonstandard when it fails (e.g. immediately terminate your program, or return <code>0</code>), or you override <code>operator new</code> to do something nonstandard when it fails.</p> <p>If your chosen approach is to immediately terminate the program, you can implement this with <code>set_new_handler()</code>, which I had forgotten about until litb reminded me.</p> <p>That leaves the problem of dealing with exceptions generated by C++ libraries you don't maintain. Generally you'll have to wrap library calls in a wrapper that looks something like this:</p> <pre><code>int DoSomething(int &amp;output, const int input) throw() { try { output = library_do_something(input); return 1; } catch (...) { return 0; } } </code></pre> <p>The <code>catch (...)</code> catches all possible C++ exceptions from <code>library_do_something</code> (as well as the assignment operator on <code>output</code>, which isn't relevant here), throws away all the information they may have contained, and then maps all those failures to <code>0</code>.</p> <p>Note that this style means that you can't use RAII at all, not even a little bit, because you have no way of signaling failure within a constructor. The whole point of RAII is that you acquire all your resources inside of constructors so that they will be properly released by a destructor during exception propagation. But resource acquisition is something that can essentially always fail. So you can't do that inside a constructor.</p>
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    1. POHow can I avoid using exceptions in C++?
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    1. USKragen Javier Sitaker
    1. USKragen Javier Sitaker
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    1. COYou can install a new handler. Operator new will call it when it doesn't have memory available, and from that handler, you can either manage to get memory or terminate the program.
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      1. USJohannes Schaub - litb
    2. COI had forgotten about `set_new_handler()`, thanks, litb! I'm updating my answer.
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      1. USKragen Javier Sitaker
    3. COJust do `kill(0,9)` instead of throwing an exception. OK, you'll also be kissing your whole process group goodbye, but that pesky exception won't be disturbing your beautiful code! ;-)
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