O'Reilly logo

HP-UX 11i Internals by Chris Moore, Chris Cooper

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Interruptions

Normally, the system executes instructions sequentially, one after the next, unless it hits a BRANCH instruction. The BRANCH instruction is covered in Chapter 2 when we talk about procedure calling conventions. The other time the system will interrupt the normal flow of processing is in the case of an interruption. An example might be an I/O card signaling that a transfer is complete or a page fault due to a page not being present in memory.

Interruptions are categorized into four classes:

  • A fault happens when the system cannot execute the current instruction due to a temporary problem, such as a page being unavailable. The instruction will usually be restarted after the condition is corrected.

  • A trap happens when the current instruction ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required