Editing INT (x86 instruction) (section)

{{Short description|Computer assembly language instruction}}
{{More citations needed |date=May 2024}}
'''INT''' is an [[assembly language]] instruction for [[x86]] [[central processing unit|processors]] that generates a [[software interrupt]]. It takes the interrupt number formatted as a [[byte]] value.<ref name="intel-ref">
{{cite book |url=https://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-instruction-set-reference-manual-325383.pdf |access-date=2024-05-23 |title=Intel® 64 and IA-32 Architectures Software Developer's Manual |volume=2 |date=March 2024 |publisher=[[Intel Corporation]] |page=3-520}}</ref>

When written in assembly language, the '''instruction''' is written like this:

:<code>INT ''X''</code>

where <code>''X''</code> is the '''''software interrupt''''' that should be generated (0-255).

As is customary with machine binary arithmetic, interrupt numbers are often written in [[hexadecimal]] form, which can be indicated with a prefix ''0x'' or with the suffix ''h''. For example, <code>[[INT 13H]]</code> will generate the 20th '''''software interrupt''''' (0x13 is nineteen (19) in hexadecimal notation, and the count starts at 0), causing the function pointed to by the 20th vector in the [[Interrupt vector table|interrupt table]] to be executed.

'''INT''' is widely used in [[real mode]]. In [[protected mode]], '''INT''' is a [[Protection ring|privileged instruction]].<ref name="intel-ref"></ref>