The GetExceptionCode function retrieves a code that identifies the type of exception that occurred. The function can be called only from within the filter expression or exception-handler block of a try-except exception handler.
Note The Microsoft C/C++ Optimizing Compiler interprets this function as a keyword, and its use outside the appropriate exception-handling syntax generates a compiler error.
DWORD GetExceptionCode(VOID)
This function has no parameters.
The return value identifies the type of exception. Following are the exception codes likely to occur due to common programming errors:
| Value | Meaning |
|---|---|
| EXCEPTION_ACCESS_VIOLATION | |
| The thread attempted to read from or write to a virtual address for which it does not have the appropriate access. | |
| EXCEPTION_BREAKPOINT | |
| A breakpoint was encountered. | |
| EXCEPTION_DATATYPE_MISALIGNMENT | |
| The thread attempted to read or write data that is misaligned on hardware that does not provide alignment. For example, 16-bit values must be aligned on 2-byte boundaries, 32-bit values on 4-byte boundaries, and so on. | |
| EXCEPTION_SINGLE_STEP | |
| A trace trap or other single-instruction mechanism signaled that one instruction has been executed. | |
| EXCEPTION_ARRAY_BOUNDS_EXCEEDED | |
| The thread attempted to access an array element that is out of bounds, and the underlying hardware supports bounds checking. | |
| EXCEPTION_FLT_DENORMAL_OPERAND | |
| One of the operands in a floating-point operation is denormal. A denormal value is one that is too small to represent as a standard floating-point value. | |
| EXCEPTION_FLT_DIVIDE_BY_ZERO | |
| The thread attempted to divide a floating-point value by a floating-point divisor of zero. | |
| EXCEPTION_FLT_INEXACT_RESULT | |
| The result of a floating-point operation cannot be represented exactly as a decimal fraction. | |
| EXCEPTION_FLT_INVALID_OPERATION | |
| This exception represents any floating-point exception not included in this list. | |
| EXCEPTION_FLT_OVERFLOW | |
| The exponent of a floating-point operation is greater than the magnitude allowed by the corresponding type. | |
| EXCEPTION_FLT_STACK_CHECK | |
| The stack overflowed or underflowed as the result of a floating-point operation. | |
| EXCEPTION_FLT_UNDERFLOW | |
| The exponent of a floating-point operation is less than the magnitude allowed by the corresponding type. | |
| EXCEPTION_INT_DIVIDE_BY_ZERO | |
| The thread attempted to divide an integer value by an integer divisor of zero. | |
| EXCEPTION_INT_OVERFLOW | |
| The result of an integer operation caused a carry out of the most significant bit of the result. | |
| EXCEPTION_PRIV_INSTRUCTION | |
| The thread attempted to execute an instruction whose operation is not allowed in the current machine mode. | |
| EXCEPTION_NONCONTINUABLE_EXCEPTION | |
| The thread attempted to continue execution after a noncontinuable exception occurred. | |
The GetExceptionCode function can be called only from within the filter expression or exception-handler block of a try-except statement. The filter expression is evaluated if an exception occurs during execution of the try block, and it determines whether the except block is executed.
The filter expression can invoke a filter function. The filter function cannot call GetExceptionCode. However, the return value of GetExceptionCode can be passed as a parameter to a filter function. The return value of the GetExceptionInformation function can also be passed as a parameter to a filter function. GetExceptionInformation returns a pointer to a structure that includes the exception-code information.
The following example shows the structure of a try-except statement.
try
{
// try block
}
except ( FilterFunction(GetExceptionCode() )
{
// exception handler block
}
In the case of nested try-except statements, each statement's filter expression is evaluated until one is evaluated as EXCEPTION_EXECUTE_HANDLER or EXCEPTION_CONTINUE_EXECUTION. Each filter expression can invoke GetExceptionCode to get the exception code.
The exception code returned is the code generated by a hardware exception, or the code specified in the RaiseException function for a software-generated exception.
When handling the breakpoint exception, it is important to increment the instruction pointer in the context record to continue from this exception.
Windows CE: The Excpt.h file has to be explicitly included in order to use GetExceptionCode.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Structured Exception Handling Overview, Structured Exception Handling Functions, GetExceptionInformation, RaiseException