Chapter 8
Quiz # 1
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 systems or different operating systems.
If their sizes are substantially different, explain why that may be the case, such as platform issues,
features, etc. Cite your sources.
Answers: A Windows 7 Operating System Requires 16 GB of Hard Disk space for (32-bit) and 20 GB for (64-bit).
A Windows 8 Operating System Requires 16 GB of Hard Disk Space for (32-bit) and 20 GB for (64-bit) which has the same requirement as a Windows 7 OS for the Hard Disk space or Secondary Storage.
For Windows XP Professional 1.5 GB or higher Hard Disk Space is needed, additional 661 MB for Service Pack 1 and 1a additional 1.8 GB for Service Pack 2 and additional 900 MB for Service Pack 3.
Sources: http://windows-operating-system-reviews.toptenreviews.com/
http://en.wikipedia.org/wiki/Windows_XP
B.Consult current literature to research file-naming conventions 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 extra credit,
explain how the File Managers for those operating systems shorten long filenames (if they do so) in their internal lists to make them easier to manipulate.
Cite your sources.
ANSWERS:
a.) Atari TOS or MiNT (MiNT is Now TOS) is a free software alternative operating system kernel for the Atari ST and its successors.
Under GEMDOS, each file located on a device is given a filename upon its creation which
serves to provide identification for the file. The filename has two parts consisting of a name
from one to eight characters long and an optional file extension of up to three characters long. If
a file extension exists, the two components are separated by a period. The extension should
serve to identify the format of the data whereas the name itself should identify the data itself.
Legal Filename Characters:
A-Z, a-z, 0-9
! @ # $ % ^ & ( )
+ - = ~ ` ; ‘ “ ,
< > | [ ] ( ) _
It's File Extensions according to sources are as follows:
1.) *.PRG - Executable program. Can be GEM programs.
2.) *.ACC - Desktop accessory. Automatically loaded.
3.) *.APP - Application (rarely encountered).
4.) *.TOS - "TOS" program that doesn't use GEM — i.e., similar to a PC's .EXE or .COM running in a CLI-mode box. The desktop clears the screen, turns on the text cursor, and hides the mouse pointer.
5.) *.TTP - "TOS takes parameters". This opens a dialog box where arguments can be added for the program. However, it converts characters to uppercase.
b.) FlexOS was a modular real-time multi-user multi-tasking operating system (RTOS) designed for computer-integrated manufacturing, laboratory, retail and financial markets.
It was developed by Digital Research's Flexible Automation Business Unit in Monterey, California since 1986 and was marketed since January 1987 as a derivation of Digital Research's Concurrent DOS 286 multiuser multitasking operating system.
It's File Extensions are listed here:
FlexOS was re-written in C for higher portability across hardware platforms, and it featured very low interrupt latency and fast context switching.
The original protected mode FlexOS 286 version 1.0 was designed for host machines equipped with 286 CPUs, and with adaptions for NEC V60, NEC V70 and Motorola 68000 processors planned. FlexOS 286 executables using the system's native INT DCh (INT 220) application program
interface had the filename extension .286. A CP/M API front end (FE) was available as well,[2] using the extension .CMD for executables.
(A filename extension of .68K was reserved for FlexOS 68K, presumably derived from Concurrent DOS 68K as of 1986.)
c.) OS/8 was the primary operating system used on the PDP-8 minicomputer developed by Digital Equipment Corporation of Maynard, Massachusetts. OS/8 was originally called MS/8 and, for a brief time, PS/8 ("Programming System/8") before Digital settled on the name OS/8 in 1971.
A virtually identical version of OS/8, called OS/12, was later used with Digital's PDP-12 computer.
Digital released OS/8 images for non-commercial purposes which can be emulated through SIMH.
It's File Extensions according to sources are as follows:
Filenames on the PDP-8 took the form of FFFFFF.XX where "F" represents an uppercase, alphanumeric character of the filename and "X" represents an upper-case, alphanumeric character of the extension (filetype).
Assembly language sources used the extension ".PA"; saved core-images (executable programs) used the extension ".SV".
The contents of any given file was stored contiguously in a single "extent". PIP included an option to compress ("squeeze") the filesystem so all unallocated space was moved to a single extent at the end of the disk.
OS/8 volumes had a very limited maximum storage size (4096 blocks) and the RK05 (2.4MB) moving-head disk exceeded this size. Because of this, RK05 cartridges were divided into two partitions.
For example the first RK05 on a system would be known as both RKA0: (SY:) and RKB0:.
This division was commonly thought to mean "the upper surface" and "the lower surface" but this was incorrect; it in fact was "the outer cylinders" and "the inner cylinders".
d.) RISC OSis a computer operating system originally designed by Acorn Computers Ltd in Cambridge, England in 1987. RISC OS was specifically designed to run on the ARM chipset, which Acorn had designed concurrently, for use in its new line of Archimedes personal computers.
It takes its name from the RISC (reduced instruction set computing) architecture supported.
File Types and Extensions: REFER HERE -- http://en.wikipedia.org/wiki/List_of_RISC_OS_filetypes
Due to it having so many to write.
Sources: http://en.wikipedia.org/wiki/MiNT#TOS_goes_multitasking_-_Enter_MultiTOS
http://en.wikipedia.org/wiki/Atari_TOS
http://dev-docs.atariforge.org/files/The_Atari_Compendium.pdf
http://en.wikipedia.org/wiki/OS/8
http://en.wikipedia.org/wiki/FlexOS
http://en.wikipedia.org/wiki/List_of_RISC_OS_filetypes
http://en.wikipedia.org/wiki/RISC_OS
According to the Reference book:
1. Explain in your own words why file deallocation is important and what would happen if it did not occur on a regular basis.
ANSWER: It is important because the File Manager is in charge of the system physical components,
its information resources, and controlling access to files -- as well as for managing the resources used by files.
If it does not occur on a regular basis then any processes waiting to access the file would not be able to progress.
2. Describe how the File Manager allocates a file in a single user. List the steps that you think would be followed and explain your reasoning.
ANSWER: The File Manager allocates a file by activating or searching or scanning first the approriate secondary storage device and then
secondly it loads the file into memory while updating it's records of who is using what file.
3. Is device independence important to the File Manager? Why or why not? Describe the consequences if that were not the case.
ANSWER:Yes, for flexibility and integrity of any or most of files when plugged in another or other operating system with hardware specifics.
Consequences, contrast to the importance, are risking the flexibility and integrity of files.
4. Do you think File retrieval is different on a menu-driven system and a command-driven system? Explain your answer and describe any differences between the two. Give an example of when each would be preferred over the other.
ANSWER: The Difference is the Interface in which they are worked with, and how it is seen by the user.
5. Imagine one real life example of each: a multi-file volume and a multi-volume file. Include a description of the media used for storage and a general description of the data in the file.
ANSWER: for a multi-file voulume a real life example would be a library or archive which contains books of many volumes in one organized room, for a multi-volume file, an example would be a box full of books inside a library in which people at the library are oblivious
as to what the box has inside.
6. As described in this chapter, files can be formatted with fixed-length fields or variable-length fields. In your opinion, would it be feasible to combine both formats in a single disk? Explain the reasons for your answer.
ANSWER: NO, it is not feasible or possible to actually combine both formats in a single disk, because both are used in different areas or aspects, a variable-length field is used on frequently in files that are most likely accessed sequentially such as text files
and program files, or files that use index to access their records while it is contrast to fixed-length fields.
7. Explain why it's difficult to support direct access to files with variable-length records. Suggest a method for handling this type of file if direct access is required.
ANSWER: Because it is hard to calculate exactly where the record is located as what's said in the reference book. If such is required then one should use the fixed-length fields because it can be easily accessed directly.
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: 1.) *.exe - PhysX_10.01.29_9.10.0129_SystemSoftware.exe
2.) *.rar - DragonAlphabet+Font.rar
3.) *.xml - Aspyrconfig.xml
