1

I'm reading through my computer organization textbook and have come across a list of events/exceptions, one of them says "Invoke the operating system from user program". What exactly does this mean?

Does this refer to a system call?

SelfStudy22
  • 27
  • 5
  • 1
    Some more context for that phrase, please…? – deceze May 05 '19 at 04:56
  • It was in a book called 'Computer Organization and Design' in a table of exceptions and interrupts. There wasn't a whole lot of context given. – SelfStudy22 May 05 '19 at 05:02
  • 3
    Processor-generated exceptions and interrupts are handled by the OS kernel. Most important side-effect is that execution mode changes to privileged mode. So yes, they do get used to make system calls as well, benefiting from the same side-effect. Googling "int 0x80 syscall" gives relevant hits. – Hans Passant May 05 '19 at 05:32

1 Answers1

1

The INVOKE directive enables a statement in a program to be processed by the operating system as if it were entered as a command from the terminal. It provides access to most operating system utilities and facilities.

Taken from this link

As it says in the link above, Use the INVOKE directive to have the operating system treat a character string from a program as an operating system command from the terminal.

Therefore, in your case, it means getting the attention of the OS from the user program using certain programming techniques.

Naser.Sadeghi
  • 1,341
  • 1
  • 12
  • 35