File system for nonvolatile memory

A nonvolatile memory medium, characterized in that it is logically divided into memory blocks of predetermined size, wherein each of said memory blocks comprises a header portion and a data portion, and wherein said header portion comprises:

• a magic number indicating whether said memory block is a valid block or a free block;
• the name of the file to which said memory block belongs;
• a flag indicating whether said memory block is the first or last block of said file;
• the block number of the next memory block comprising said file, if any;
• and
• the length of valid data in said data portion of said memory block.

A method for opening an existing file stored on a nonvolatile memory medium, comprising:

• scanning said nonvolatile memory medium in sizes of one predetermined logical block;
• for each said logical block, reading a block header containing a magic number;
• testing said magic number to determine whether said logical block is a valid block or a free block, and if said logical block is a valid block, performing a comparison of a file name encoded within said block header with a specified file name to be opened;
• testing a flag within said block header indicating to determine whether said logical block is the first block of said specified file, if said comparison produces a match;
• and
• returning to said scanning step with the next logical block until either said comparison produces a match or all the blocks have been tested, thereby indicating an error condition.

A method for opening a new file to be stored on a nonvolatile memory medium, comprising:

• scanning said nonvolatile memory medium in sizes of one predetermined logical block;
• for each said logical block, reading a block header containing a magic number;
• testing said magic number to determine whether said logical block is a valid block or a free block, and if said logical block is a free block, modifying said block header to comprise a valid magic number, the name of the file to be opened, and flags indicating whether said logical block is either the first block or the last block of said file;
• and
• returning to said scanning step with the next logical block until either said testing step has identified a free block or all the blocks have been tested, thereby indicating an error condition.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform a method for opening an existing file stored on a nonvolatile memory medium, the method comprising:

• scanning said nonvolatile memory medium in sizes of one predetermined logical block;
• for each said logical block, reading a block header containing a magic number;
• testing said magic number to determine whether said logical block is a valid block or a free block, and if said logical block is a valid block, performing a comparison of a file name encoded within said block header with a specified file name to be opened;
• testing a flag within said block header indicating to determine whether said logical block is the first block of said specified file, if said comparison produces a match;
• and
• returning to said scanning step with the next logical block until either said comparison produces a match or all the blocks have been tested, thereby indicating an error condition.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by the machine to perform a method for opening a new file to be stored on a nonvolatile memory medium, comprising:

• scanning said nonvolatile memory medium in sizes of one predetermined logical block;
• for each said logical block, reading a block header containing a magic number;
• testing said magic number to determine whether said logical block is a valid block or a free block, and if said logical block is a free block, modifying said block header to comprise a valid magic number, the name of the file to be opened, and flags indicating whether said logical block is either the first block or the last block of said file;
• and
• returning to said scanning step with the next logical block until either said testing step has identified a free block or all the blocks have been tested, thereby indicating an error condition.