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Why is INT3 special?

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I have no idea what INT(3) does. That is, if you use the "INT <immediate>" form of the INT instruction, and you supply a "3" as the numeric operand, then what is the mnemonic for that instruction? Is the two-byte "INT 3" defined to have the same semantics as the one-byte INT 3?

The opcode for INT 3 is 0xCC, as opposite from the opcode for INT immediate, which is 0xCD imm8. According to Intel documentation: "Intel and Microsoft assemblers will not generate the CD03 opcode from any mnemonic" and 0xCC has some special features, which are not shared by "the normal 2-byte opcode for INT 3 (CD03)"..
IA-32 Intel® Architecture Software Developer’s Manual. Volume 2A (Instruction Set Reference, A-M). Order no. 253666.
Rjgodoy (talk) 04:50, 28 March 2008 (UTC)[reply]
I think the explanation clarifies the section about INT 3, then I moved it there. Rjgodoy (talk) 07:21, 10 October 2008 (UTC)[reply]
I posit that, being a single byte, it's possible to fill any gap with INT3. Moreover, and probably more importantly, any byte will be an instruction, so that there is no synchronisation problem. All the best: Rich Farmbrough 09:13, 8 January 2024 (UTC).[reply]

Proposed merge with Interrupt descriptor table

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The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.
No consensus so do not merge Shhhnotsoloud (talk) 10:26, 11 April 2017 (UTC)[reply]

There should probably be a "x86 interrupts" article into which these two should be merged, given the quite large overlap between topics.

Also, take a look at the Interrupt vector table article — supposedly about the generic concept, but already sidetracked by details about x86, which would also belong here. Keφr 13:18, 23 August 2014 (UTC)[reply]

Nope they are different - One page is the BIOS interrupts and the other is a general IVT article. I say don't merge them or you will have many unhappy people such as the group of us who are making an OS. Many people use the first article for BIOS interrupts and the second for more info on how to set up the IVT. Do not merge — Preceding unsigned comment added by 96.50.80.149 (talkcontribs)
They may be different, but there is so much overlap that it matters very little. There is no reason that both cannot be discussed in a single article. And people who make OSes are better served by osdev.org anyway. —Keφr 16:23, 22 August 2015 (UTC)[reply]

'* I mourn the wasted CPU cycles.' - at this point i'm not even sure you know what they are — Preceding unsigned comment added by 101.163.76.148 (talk) 09:46, 4 November 2016 (UTC)[reply]

(non-admin closure)
The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.