|
|
NM callable only.
This routine can be used to efficiently move data from a source
buffer to a target buffer. If the source and target buffers were
viewed horizontally, like a line of text, the data movement is performed
by starting at leftmost position of the source buffer (to the leftmost position
of the target buffer) and proceeding to the rightmost.
Syntax
I64 @64 @64 I32
HPFMOVEDATALTOR (count, source_ptr, target_ptr, status);
Parameters
- count
64-bit signed integer by reference (required)
The count parameter allows the caller to specify the number of bytes to
move from the source buffer to the target buffer.
- source_ptr
64-bit pointer by value (required)
The source_ptr can be a 64-bit pointer to any valid object that the
calling process has access to. The buffer may be in the caller's stack,
heap, or obtained by opening a file with user mapped access
- target_ptr
64-bit pointer by value (required)
The target_ptr can be a 64-bi pointer to any valid object that the
calling process has access to. The buffer may be in the caller's stack,
heap, or obtained by opening a file with user mapped access.
- status
32-bit signed integer by reference (optional)
Returns the status of the HPFMOVEDATALTOR call. If no errors or warnings
are encountered, status returns 32 bits of zero. If errors or warnings
are encountered, status is interpretted as two 16-bit fields. Bits
(0:16) comprise status.info. A negative value indicates an error
condition, and a positive value indicates a warning condition. Bits
(16:16) comprise status.subsys. The value represents the subsystem that
set the status information.
Operation Notes
This intrinsic is especially useful when the source and target
buffers are overlapping. The HPFMOVEDATALTOR intrinsic is typically
used when the target buffer's address is to the left (smaller)
of the source buffer's address. Moving the data from the
left to the right ensures that the data in the source buffer is
copied to the target buffer before it is overwritten itself.
Related Information
- Manual
Accessing Files Programmer's Guide
|