There are no exceptions in C. In C the errors are notified by the returned value of the function, the exit value of the process, signals to the process (Program Error Signals (GNU libc)) or the CPU hardware interruption (or other notification error form the CPU if there is)(How processor handles the case of division by zero).
Exceptions are defined in C++ and other languages though. Exception handling in C++ is specified in the C++ standard "S.15 Exception handling", there is no equivalent section in the C standard.
Answer from Brian R. Bondy on Stack OverflowThere are no exceptions in C. In C the errors are notified by the returned value of the function, the exit value of the process, signals to the process (Program Error Signals (GNU libc)) or the CPU hardware interruption (or other notification error form the CPU if there is)(How processor handles the case of division by zero).
Exceptions are defined in C++ and other languages though. Exception handling in C++ is specified in the C++ standard "S.15 Exception handling", there is no equivalent section in the C standard.
In C you could use the combination of the setjmp() and longjmp() functions, defined in setjmp.h. Example from Wikipedia
#include <stdio.h>
#include <setjmp.h>
static jmp_buf buf;
void second(void) {
printf("second\n"); // prints
longjmp(buf,1); // jumps back to where setjmp
// was called - making setjmp now return 1
}
void first(void) {
second();
printf("first\n"); // does not print
}
int main() {
if ( ! setjmp(buf) ) {
first(); // when executed, setjmp returns 0
} else { // when longjmp jumps back, setjmp returns 1
printf("main"); // prints
}
return 0;
}
Note: I would actually advise you not to use them as they work awful with C++ (destructors of local objects wouldn't get called) and it is really hard to understand what is going on. Return some kind of error instead.
Is there a way to simulate c++ exceptions logic in C? error handling with manual stack unwinding in C is so frustrating
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I've written in C as a student for about a year now. I'm wondering what are some techniques for error handling? C doesn't really have a try-catch mechanism. I generally just return error values like -1 or 0 or NULL, but are there any other ways to handle errors?
I've been stuck on a extremely simple problem for hours, I'm a sophomore in comp sci and never dealt with exceptions before and all the solutions I find online seem to not work.
All I need to do is throw a runtime error if the argument for my function is less than 0. I'm pretty sure catch comes after try. But our professor is having us use Catch 2 framework. And we need to use CHECK THROWS as well. I'm not really sure how this is all supposed to work together if someone could explain the format this would take and what exactly is happening it would be much appreciated. I don't want to post the entire program as our professor told us only to ask for help for specific problems
try{
if(n<0){
throw std::runtime_error("error");
}
}
catch{}CHECK_THROWS(factorial(-3));
throw usually causes the function to terminate immediately, so you even if you do put any code after it (inside the same block), it won't execute. This goes for both C++ and C#. However, if you throw an exception inside a try block and the exception gets caught, execution will continue in the appropriate catch block, and if there is a finally block (C# only), it will be executed whether an exception is thrown or not. At any rate, any code immediately after the throw will never be executed.
(Note that having a throw directly inside a try/catch is usually a design problem - exceptions are designed for bubbling errors up across functions, not for error handling within a function.)
No, you don't need to return, because after the exception is thrown the code after that wont' be executed.