In MS-DOS file system, open system call is used for reading a file. Relative or absolute path name is used for making an open system call. MS-DOS file system is used in Windows, digital cameras, and mp 3 players. MS-DOS directory entry is of 32 bytes.
Here are the fields in MS-DOS directory entry:
1) FN represents file name. It has a size of 8 bytes.
2) E represents an extension for the file name. It has a size of 3 bytes.
3) AT represents attributes. It has a size of 1 byte. The single bit is used to specify if a file is a file is a system file, is read-only, has to be archived, or if it is hidden.
4) R represents reserved bits. It has a size of 10 bytes.
5) T represents time field which keeps the information about time when a file was created. It has a size of 2 bytes. Time field is further divided to seconds, minutes, and hours.
6) DT represents date field which keeps the information about date when a file was created. It has a size of 2 bytes. Date field is further divided in day, month, and year.
7) FBN represents first block number. It has a size of 2 bytes. First block number acts as an index for an entry in file allocation table.
8) S represents file size. It has a size of 4 bytes.