How can I ensure that integer arithmetic doesnt overflow?

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The usual approach is to test the operands against the limits in the header file <limits.h> before doing the operation. For example, here is a ``careful'' addition function:

int
chkadd(int a, int b)
{
if(INT_MAX - b < a) {
fputs("int overflow\n", stderr);
return INT_MAX;
}
return a + b;
}

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How can I trap or ignore keyboard interrupts like control-C? The basic step is to call signal, either as #include <signal.h> signal(SIGINT, SIG_IGN); to ignore the interrupt signal, or as extern void func(int); signal(SIGINT, func); to cause control to transfer to function func on receipt of ... 2015-03-06, 1076👍, 0💬

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