Operating Sytem

Question 1

What is real-time transaction processing

with examples

Answer 1

• Response must be very short, hence immediate to inputs
• Outputs can affect source of input so processing must be fast
• Can usually handle multiple, simultaneous input

E.g Travel agent/Theatre booking:

• A seat is book and record is updated quickly
• it is locked during an update, quickly decreasing availability by 1
• This avoids double bookings
• Output tickets on screen or via automated email.

Question 2

What is Batch processing

-How does it work?

Answer 2

Preforms many similar tasks in a sequence without need for user intervention e.g printing of bill/ payroll

How it works:

• Data is used by batch processing
• stored in a temporary file over short period of time
• Merged with master file at regular time interval
  e. g
• Employees clock in/out of work (timesheet of hours ) collected and stored over weekly/monthly file
• At end of mont temp file merged with master file
• At end of month wages are calculated using masterful in a batch process - wages are derived and payrolls printed out

Question 3

What is real-time control processing?

Answer 3

• Inputs are processed very quickly
• Needs to be quick enough to deliver output on time
• Output adjusted accordingly
• This means accidents can be avoided

e. g
- nuclear power station to control reactor temp by continuously checking temp which is inputted to the system
- Automated fish tank, automated green house, rear car parking control system aircraft systems, life support systems, safety-critical systems
- Would output via actuators and input via sensors

Question 4

What is file manager utility

Answer 4

enables user to do simple file manipulation
Tasks file management can do on its own:
- Move files from one directory to another
-Copy files
-Rename files
-List directory contents

cannot open files -that is responsibility of application associated with file e.g docx is associated with word