$GET ALIGN FAULT DATA
$GET_ALIGN_FAULT_DATA (Alpha and I64) is a system service that obtains data from the user image alignment fault buffer if buffered user alignment fault data reporting has been enabled. This service accepts 64-bit addresses. When buffered user alignment fault data reporting is enabled, the operating system writes each alignment fault into a user-defined buffer. The user must poll this buffer periodically to read the data.
The user must call the $START_ALIGN_FAULT_REPORT service to enable buffered user alignment fault data reporting. For more information about buffered user alignment fault data reporting, see the $START_ALIGN_FAULT_REPORT system service.
Contents
Format
SYS$GET_ALIGN_FAULT_DATA buffer ,buffer_size ,return_size
C Prototype:
int sys$get_align_fault_data (void *buffer, int buffer_size, int *return_size);
Arguments
buffer
| OpenVMS usage: | address |
| Type: | longword (unsigned) |
| Access: | read/write |
| Mechanism: | by 32- or 64-bit reference |
The user buffer in which the alignment fault data is to be stored. The buffer is the 32- or 64-bit address of this user buffer.
buffer_size
| OpenVMS usage: | byte count |
| Type: | longword (signed) |
| Access: | read |
| Mechanism: | by value |
The size, in bytes, of the buffer specified by the buffer argument.
return_size
| OpenVMS usage: | longword_signed |
| Type: | longword (signed) |
| Access: | write |
| Mechanism: | by 32- or 64-bit reference |
The amount of data, in bytes, stored in the buffer. The return_size argument is the 32- or 64-bit address of a naturally aligned longword into which the service returns the size of the buffer. The return_size is set to 0 if there is no data in the buffer.
Condition Values Returned
| Value | Description |
|---|---|
| SS$_NORMAL | The service completed successfully. |
| SS$_ACCVIO | The buffer named in the buffer argument is not accessible. |
| SS$_AFR_NOT_ENABLED | Alignment fault reporting has not been enabled. |
| SS$_BADPARAM | The buffer size is smaller than the minimum defined by the AFR$K_USER_LENGTH symbol. |
Privileges Required
None
Quota Required
None
