Patent ID: 7779181

Claim:
A computer readable storage medium comprising a device driver comprising: logic configured to allocate clusters on a file allocation table for a buffer file for buffer space on a disk and to cause media content instances to be written to the buffer space; the file allocation table comprising: a first data structure comprising file list entries for files, wherein the file list entries include the clusters allocated for each of the files; and a second data structure comprising cluster list entries for the clusters, wherein the cluster list entries identify the clusters and a quantity of the files that simultaneously share each one of the clusters; logic configured to limit the buffer file to a substantially constant buffer file size, such that when the buffer file approaches a full status, a cluster storing the oldest media content is first deallocated from the buffer file and a new cluster is correspondingly allocated to the buffer file; and logic configured to maintain the buffer space as substantially constant in size by autonomously and automatically removing buffer space clusters designated for a permanent recording and replacing the removed buffer space clusters with replacement clusters without intervention or further instruction from the device driver.