LinuxQuestions.org - try catch(...)

- Linux - Newbie (https://www.linuxquestions.org/questions/linux-newbie-8/)

- - try catch(...) (https://www.linuxquestions.org/questions/linux-newbie-8/try-catch-196356/)

I am a windows programmer who is porting an app to linux. It is going well so far but I am hitting a seg-fault. My error handing code seems to be at issue.

Code

try {
ReallyUglyFunction(); //throw lots of std::exceptions plus many others including divide by zero or referencing bad memory
}
catch (exception e) {
// catches what I expect
}
catch (...) {
// never catches anything in linux
}

In Windows catch(...) is a fail safe that catches everything.
In Linux catch(...) doesn't seem to catch anything.

What do I need to do to fix this?

Thanks

From what I've seen, errors like division by zero and segmentation violations result in signals being forced on a process by the kernel. You can install signal handlers in your C++ program like so:

Code:

#include <exception>

#include <iostream>

#include <signal.h>



using namespace std;



void sighandler(int);



void sighandler(int signum)

{

  switch(signum)

    {

    case 8:  cout << "Caught SIGFPE\n"; exit(1);

    case 11: cout << "Caught SIGSEGV\n"; exit(2);

    default: cout << "I shouldn't be here!\n";

    }

}



int main(void)

{

  int a = 1, b = 0;

  int* d = 0;



  if (signal(SIGFPE, &sighandler) == SIG_ERR)

      cout << "Couldn't install FPE signal handler!\nExpect a core dump\n";

  if (signal(SIGSEGV, &sighandler) == SIG_ERR)

      cout << "Couldn't install SEGV signal handler!\nExpect a core dump\n";



#ifndef SKIP

  cout << "Div by zero\n";

  int c = a/b;

#else

  cout << "Playing with bad memory\n";

  d[0] = 0;

#endif

}

Once you've run and compiled, you should get

Code:

[mascdman@odin tmp][ :) ]$ ./a.out 

Div by zero

Caught SIGFPE

[mascdman@odin tmp][ :( 1 ]$

Code:

[mascdman@odin tmp][ :) ]$ ./a.out 

Playing with bad memory

Caught SIGSEGV

[mascdman@odin tmp][ :( 2 ]$

To get a list of other signals, run man -S 7 signal. Hope this helps.

--mascdman

Re: try catch(...)

Quote:

Originally posted by Sinner6
try {
ReallyUglyFunction(); //throw lots of std::exceptions plus many others including divide by zero or referencing bad memory
}
catch (exception e) {
// catches what I expect
}
catch (...) {
// never catches anything in linux
}

Can you be more specific? Like in actually posting some
code, including the output you get on screen?

Cheers,
Tink

I think I have things back under control.
Thanks for all the help.