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I was just wondering if a system exception like say divide by zero actually "throws" something to the application. Would it be possible to catch this somehow by default?.

i mean we can define a custom divide fn which checks for null divisor and throws an exception, but just thought it would be nice if this exception was thrown by default

//say I do this int i; try { i /= 0; // My compiler (gcc) did warn abt the divide by zero :-) } catch (...) { // Can we get here for this case? }
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Reset to default
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This is OS-dependent. You can do it in Visual C++ code on Windows - catch(...) will also catch so-called structured exceptions that include divisions by zero, access violations, etc., but not in gcc-compiled code on Linux.

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The key observation here is that dividing by 0 is undefined behaviour as far as the C++ standard is concerned. This means individual implementations can do what they like - interrupt the process with a signal, throw an exception, phone your boss and tell him you can't code for toffee, whatever.
For Windows you could use SetUnhandledExceptionFilter to install an handler which in turn could throw C++ exceptions, e.g. derived from std::exception.
You need to turn on /EHa to catch divide by zero, etc in Visual C++: msdn.microsoft.com/en-us/library/1deeycx5%28VS.80%29.aspx
Thanks guys.. I didn't know the fact that this one was undefined in C++.
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The C++ Standard does not say that divide by zero throws an exception - it says that it is undefined behaviour.

Also, when you say:

i /= 0; // My compiler (gcc) did warn abt the divide by zero :-)

the compiler can only give the warning if the thing you divide by is a constant.

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