Exception handling syntax: Difference between revisions

Revision as of 11:38, 28 June 2007

Revision as of 11:40, 28 June 2007

Line 217:

The most common way to implement exception handling in standard C

is to use [[setjmp/longjmp]] functions:

<source lang=c>

#include <setjmp.h>

#include <stdio.h>

enum { SOME_EXCEPTION = 1 };

jmp_buf state;

int main()

{

int exception;

if((exception = setjmp(state)) == 0) // try

{

if(/* something happened */)

longjmp(state, SOME_EXCEPTION); // throw SOME_EXCEPTION

}

else switch(exception)

{

case SOME_EXCEPTION: // catch SOME_EXCEPTION

puts("SOME_EXCEPTION caught");

break;

default: // catch ...

puts("Some strange exception");

}

return 0;

}

</source>

Some [[operating system]]s also have similar features, for example [[Microsoft Windows]] has "[[Structured Exception Handling]]" (SEH):

#include <setjmp.h>

<source lang=c>

#include <stdio.h>

int filterExpression (EXCEPTION_POINTERS* ep) {

enum { SOME_EXCEPTION = 1 };

++ep->ContextRecord->Eip;

jmp_buf state;

return EXCEPTION_CONTINUE_EXECUTION;

int main()

}

{

int main() {

int exception;

static int zero;

if((exception = setjmp(state)) == 0) // try

__try {

if(/* something happenedzero = *1/)zero;

printf ("Past the exception.\n");

longjmp(state, SOME_EXCEPTION); // throw SOME_EXCEPTION

} __except (filterExpression (GetExceptionInformation())) {

}

printf ("Handler called.\n");

else switch(exception)

{

case SOME_EXCEPTION: // catch SOME_EXCEPTION

puts("SOME_EXCEPTION caught");

break;

default: // catch ...

puts("Some strange exception");

}

return 0;

}

</source>

Some [[operating system]]s also have similar features, for example [[Microsoft Windows]] has "[[Structured Exception Handling]]" (SEH):

int filterExpression (EXCEPTION_POINTERS* ep) {

++ep->ContextRecord->Eip;

return EXCEPTION_CONTINUE_EXECUTION;

}

int main() {

static int zero;

__try {

zero = 1/zero;

printf ("Past the exception.\n");

} __except (filterExpression (GetExceptionInformation())) {

printf ("Handler called.\n");

}

return 0;

}

* see also [[Vectored Exception Handling]] (VEH).