Hello, When an int 13 operation is handles (suppose read), you are supposed to get sector X up until sector Y, where X is lba and count is Y. But I wonder, the buffer is the size of the operation? or is it a predefined size that never changes? I tend to incline for the later one, but how can I determine the size? Thanks, Daniel -- +-=====---------------------------+ | +---------------------------------+ | This space intentionally blank for notetaking. | |   | Daniel Castro,                | | |   | Consultant/Programmer.| | |   | U Andes                         | +-------------------------------------+