System for updating data stored on a flash-erasable, programmable, read-only memory (FEPROM) based upon predetermined bit value of indicating pointers

A computer file storage system for organizing files based on a hierarchical directory structure, the directory structure having a plurality of directory entries, the computer file storage system comprising:

• a computer having a memory for storing directory entries, the memory comprising a plurality of bits such that once a bit is changed from a predefined bit value to another bit value the changed bit cannot be individually changed back to the predefined bit value;
• means for allocating a portion of the memory for storing a directory entry, the directory entry having a primary pointer, an indicator, and a sibling pointer, the directory entry primary pointer, indicator, and sibling pointer having a plurality of bits initially being set to the predefined bit value;
• means for storing directory data in the directory entry;
• means for setting the sibling pointer of the directory entry to point to another directory entry at the same level in the directory structure to form a linked list of sibling directory entries;
• means for setting the primary pointer of the directory entry to point to another directory entry at the next level lower in the directory structure;
• means for determining whether at least one bit of the indicator is not set to the predefined bit value to indicate that the directory data of the directory entry has been superseded;
• and
• means for setting the indicator of the directory entry to point to a superseding directory entry and to indicate that the directory data of the directory entry has been superseded by changing at least one bit of the indicator from the predefined bit value to the other bit value, the superseding directory entry to contain updated data for the directory entry.

A computer file storage system for storing files, the computer file storage system comprising:

• a computer having a memory for storing files, the memory comprising a plurality of bits such that once a bit is changed from a predefined bit value to another bit value the changed bit cannot be individually changed back to the predefined bit value;
• means for allocating a portion of the memory for storing a file entry, the file entry to contain information relating to a file and containing an indicator and a sibling pointer, the file entry information, indicator, and sibling pointer having a plurality of bits initially being set to the predefined bit value;
• means for storing information relating to the file in the file entry;
• means for setting the sibling pointer of the file entry to point to another file entry to form a linked list of file entries;
• means for determining whether at least one bit of the indicator is not set to the predefined bit value to indicate that the information of the file entry has been superseded;
• and
• means for setting the indicator of the file entry to point to a superseding file entry and to indicate that the information of the file entry has been superseded by changing at least one bit of the indicator from the predefined bit value to the other bit value, the superseding file entry to contain updated information for the file entry.

A method of updating data stored on a computer memory device with new data, the memory device containing records of data, each record having an indicator, the method comprising the steps of:

• locating a record that contains data to be updated, the record being contained in the memory device comprising a plurality of bits such that once a bit is changed from a predefined bit value to another bit value the changed bit cannot be individually changed back to the predefined bit value, the data including bits that have been changed from the predefined bit value to the other bit value, the indicator of the located record having each bit set to the predefined bit value;
• allocating a record to contain the new data, the record being allocated in the memory device, each bit of the allocated record being set to the predefined bit value;
• writing the new data to the allocated record;
• and
• setting the indicator in the located record to point to the allocated record and to indicate that the new data in the allocated record is an update of the data in the located record by changing at least one bit of the indicator from the predefined bit value to the other bit value,
• wherein the step of locating a record includes the step of determining an address of a first unallocated location in the memory device.