IT221

A.)  Research the size of operating system software by finding the amount of secondary storage (disk) space required by different versions of the same operating system or  different operating system. If their sizes are substantially different ,explain why that may be the case, such as such platform issues ,features,etc.

Answer:

Win 3.1 ~15MB, although it requires at least MS-DOS 6.22 to boot, so tack on another few megs.

Win 95 b ~80MB

Win 98 SE ~300MB

Win 2000 Pro ~720MB with no service packs. After SP4, it's around 1GB.

Win XP Pro, ~1.2GB with SP2.

Suse 9.2

Slackware 10.1

Ubuntu

Linspire 4.5

Mandriva 10.1

B.) Consult current literature to research file-naming conversations for four different operating systems(not including UNIX,MS-DOS,Windows, or Linux).Note the acceptable range of characters,maximum length,case sensitivity,etc.Give examples of both acceptable and unacceptable  filenames . For For extra credit,explain how the File Managers for those operating systems shorthen long filenames in their internal list to make them easier to manipulate.Cite your sources.

Answer:

DEC VAX VMSAcceptable range of characters – A-Z 0-9 $ - _Maximum length – 255 file name & 32 extensionsCase sensitivity – insensitiveReserved Characters – noneAcceptable – kL209_pp.doxUnacceptable – fill\this.t!LISO 9660Acceptable range of characters – A-Z 0-9 _ .Maximum length – 255 file name Case sensitivity – insensitiveReserved Characters – noneAcceptable – kL209_pp.doxUnacceptable – fill\this.t!LMAC OS HFSAcceptable range of characters – 8-bit setMaximum length – 255 file name Case sensitivity – insensitive & perservationReserved Characters – :Acceptable – kL209_pp.doxUnacceptable – fill:this.t!L

Exercises

1.Explain in your own words why file deal location is important and what would happen if it did not occur on a regular basis.

Answer:

 It really depends on the operating system. Most modern operating systems will deallocate all files assigned to a process when the process terminates, and will flush all internal I/O buffers prior to that, so closing files is mainly a question of neatness, not necessity.
Some bound I/O management libraries may retain internal application-side buffers that aren't flushed unless the file is explicitly closed. In these cases, you might need to close a file before terminating in order to avoid file corruption or lost updates. But that is relatively rare these days.

2. Describe how the File manager allocates a file to a single user. List the steps that you think would be followed and explain you reason.

Answer:
 •the File Manager handles all files on secondary storage media. To perform these tasks, file management     must:
              -Identify the numerous files by giving unique names to them
              -Maintain a list telling where exactly each file is stored, how many sectors on 
                the medium it
              -Occupies, and in which order those sectors make up the file
              -Provide simple and fast algorithms to read and write files in cooperation 
               with the device manager
              -Give and deny access rights on files to users and programs
              -Allocate and deallocate files to processes in cooperation with the process manager
              -Provide users and programs with simple commands for file handling

3.Is device independence important To the File Manager?  Why or Why not? Describe the consequences if that were not the case.

Answer:
Device Independence is important to the File Manager because it processes making a software application be able to function on a wide variety of devices regardless of the local hardware on which the software is used

4.Do you think file retrieval is different on a menu-driven system  and a command-driven system?

Answer:
All these processes were the same such that they do not automatically eradicate a file but prompt for the user's confirmation. But they also differ and matters on how fast and easier the user could take a request.

5.Image one real-life example of each: a multi-file volume and a multi-volume file. Include a description of the media used for storage sand a general description of the data on the file.

Answer:

In real life the multi-file volume is just like our life that is  only one  which only god can manage and knows our life will end.

As multi-volumes files is just like the Gods love which he share in his people and his peopleshare their love back at him.

6.As described in the chapter, files can be formatted with fixed-length fields or variable-length. In your own opinion, would it be feasible to combine both formats in a single disk? Explain the reasons for your answer.

Answer:

No,its not feasible to combine both formats in a single disk because the two fields are in different areas.

7.Explain why it’s difficult to support  direct access to file with variables-length records. Suggest a method for handling this type of file is direct access is required.

Answer:

It is difficult to direct access because it is hard to find the exact location of records ,such as we suggest the variable-length record because  it is the easy to access file directly at the period of time.

8.Give an example of the names of three files from your own PC that do not reside at the root or master directory. For each file, list both the relative filename and it's complete filename.

Answer:
   •exe - 1701_Gold_Trn_P.exe
    •ttf - Dovah.ttf
    •pdf - 1701AD_GOLD_Manual.pdf