ch5 Flashcards
Explain why a computer system requires an Operating System (OS)
1-loading a software for the user to interact with
2- managing hardware resources such as memory and devices
3- authentications and security
4- file management
5- handling input and output devices
operating system
software that provides environment in which applications can run and provides an interface between hardware and human operators
operating system tasks
1- file management
2- memory management
3- hardware management
4- process management
5- security management
what is memory management
it is a process of controlling and coordinating a computer’s main memory
memory management tasks
1- memory optimisation: allocates and deallocates RAM to tasks
keeps track of allocated and free memory location
swaps data from and to hard drive
2- memory orginisation: handles virtual memory
segmentation
3- memory protection: ensure that two competing applications do not use the same memory locations at the same time
security management
part of the operating system that ensures the integrity and availability of data
tasks of security management
1- automatic backup
2- maintaining access rights
3- authentication: checks the users username and password
4- carrying out operating system updates when available
5- sets up users account
process management
part of operation system that involves the allocation of resources and permits the exchange of data
tasks of file management
1- controls access
2- maintains directory structure
3- specifies tasks that can be performed on a file
4- provides file naming conventions
hardware management
part of the operating system
that controls all input/output devices connected to a computer (has sub-management systems)
tasks of printer management
1- sends data to printer queue
2- handles error messages
3- sends control commands
4- installs printer driver
types of utility programs
1- disk formator
2- virus checker
3- disk repair software
4- defragmentation software
5- file compression
6- backup software
pros of using program library
1- pre tested so it saves testing time
2- pre written so save time since less program is written
3- can be complex algorithms that are hard for some people cant code
cons of using program library
1- can be changed which produces an unexpected result
2-not guaranteed through testing may produce unexpected bug or virus
pros of using dll
1- executable file is smaller since its only loaded into memory when required
2- change is done to the dll independently so recompiling the whole program is not required
3- can be available to many applications at the same time so save storage
benefits of compiler
1- produces an executable file
2- compiler code is executed faster
3-once translated the compiler software is not needed to run the program
4- can be tested multiple times without needing to retranslate it each time
benefits of interpreter
1- easier to debug
2- the interpreter is stopped when an error is found
3- error can be corrected in real time
Integrated development environment (IDE)
a suite of programs used to write and test a computers program written in high level language
single stepping
run the code line by line so that the values are checked
breakpoint
stops the code at a specific line to check the current values
report window
a separate window in the run-time part of the IDE that shows the contents of the variables during execution of program
dynamic syntax checker
underline syntax error as code is entered
context sensitive prompt
automatically complete a statement
IDE tools used to help the writing of the program
1- debugging tool
2-pretty printing
3- context sensitive prompt
4- auto-correct
