Do you want BuboFlash to help you learning these things? Or do you want to add or correct something? Click here to log in or create user.

The MS-DOS operating system is an example of a single-tasking system. It has a command interpreter that is invoked when the computer is started (Figure 2.9(a)). Because MS-DOS is single-tasking, it uses a simple method to run a program and does not create a new process. It loads the program into memory, writing over most of itself to give the program as much memory as possible (Figure 2.9(b)). Next, it sets the instruction pointer to the first instruction of the program. The program then runs, and either an error causes a trap, or the program executes a system call to terminate. In either case, the error code is saved in the system memory for later use. Following this action, the small portion of the command interpreter that was not overwritten resumes execution. Its first task is to reload the rest of the command interpreter from disk. Then the command interpreter makes the previous error code available to the user or to the next program
If you want to change selection, open document below and click on "Move attachment"


  • owner: miller - (no access) - Abraham Silberschatz_ Peter B Galvin_ Greg Gagne -Operating system concepts-Wiley (2012).pdf, p94
  • owner: hughleat - (no access) - Abraham-Silberschatz-Operating-System-Concepts---9th2012.12.pdf, p94


statusnot read reprioritisations
last reprioritisation on suggested re-reading day
started reading on finished reading on



Do you want to join discussion? Click here to log in or create user.