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Why hide such a handsome piece of handiwork?，推荐阅读快连下载安装获取更多信息
2024年12月23日 星期一 新京报，推荐阅读一键获取谷歌浏览器下载获取更多信息
Real-mode programs freely execute CLI and STI to control interrupts, PUSHF and POPF to manipulate flags, INT n for DOS and BIOS calls, and IN/OUT for hardware I/O. In normal protected mode, these instructions are privilege-checked -- they execute normally if the caller has sufficient privilege, and fault otherwise. The 386 can't simply let V86 tasks execute them freely -- a DOS program disabling interrupts would bring down the whole system -- but trapping on every INT 21h call would make V86 impractically slow.
Feb. 26, 2026 at 12:22 p.m. PT