6.1.1 setting the file name.The aim in designing an operating system is required to provide as the user freedom from any device (device independent), so in any active data session China holding the audit file must have the same format. In addition, a method of holding the audit file for any active data you do not need to define the details, difficult flurry to treetop dresses. Just specify the name and the file name extension, it is enough.To determine the name of the file for each operating system that is different? But in most cases, there will be a similar requirement. Some operating systems make up the name begins with character and is followed by a digit or a letter of no more than 8 characters, some operating systems require freely name cannot exceed 255;In some operating systems, the system set the name with a small capital letters is not the same as the UNIX name if this is a big must be referred to by the President as well. If a reference with the same name is treated as a separate. For example, Name, NAME, name, if the file is considered UNIX 3 different files etc but for MS-DOS are treated as the same name in the Windows 95, Windows NT and Windows 2000 ฏ้ยังคง using the file system the same way as the MS-DOS.In most cases, the operating system file name is composed of two parts: the primary name. Each file extension (file extension) both are stage with MS-DOS system points (period) in the parent's name will contain a 1 to 8 together and then followed by another extension may not exceed 3 a, etc, but for a UNIX system may have more than one extension part, such as prog.c.z.6.1.2 file structureStructured files that are commonly used are 3 ways: as the first method 6.1 (a 6.1.) are stored as bytes, primarily contiguous to the operating system, such as UNIX and Windows to keep the file in this manner, as there are no storage structure. A new file that is created will be brought together to study until the space is full. By the operating system itself, rarely serve anything. The second way (Figure 6.1 b) keep a record by one the size of a fixed rekdod to each file is stored in the form of specially arranged to consecutive records sequentially until the last record. The last record may not be full of records it. To read, write, will go to the individual records. In some operating systems, the system may be assigned to each record size is equal to 80 letters, which equals 1-line fit. This method is used in the CP/M operating system section of the third way (Figure 6.1 c) stored as a tree or a tree (tree) of the block. Tae block consists of records, with the size of the records based on several factors, such as size, file time information used in the active session data (Access time), etc. This method is used in several computer operating systems together.
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